University of Groningen
Qualitative comparison of Dutch and Ethiopian Rose production systems. Why Dutch
rose growers move to African Nations and what consequences does this migration
have?
Vries de, Willem
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Qualitative comparison of Dutch and
Ethiopian rose production systems
Why Dutch rose growers move to African nations and what consequences does this
migration have?
Training thesis of Willem de Vries
Msc student 'Energy & Environmental Studies'
University of Groningen
May 2010
With thanks to my supervisors
Dr. ir. S. Nonhebel
+31 (0) 50 363 4611
[email protected]
Prof. dr. A.P. Grootjans
+31 (0) 50 363 4605
[email protected]
Preface
In this report I describe my research on the differences between the Dutch and the Ethiopian rose
cultivation system. This was done to acquire a better insight in the general differences between the
agricultural systems producing vegetables, fruits and flowers in the Netherlands and their competitors in
warmer countries.
For this report I owe special thanks to my supervisors at the University of Groningen. My first supervisor
Dr. Ir. Sanderine Nonhebel and my second supervisor Dr. Ab P. Grootjans were of great help during my
research. Beside of these two persons, I would like to thank the two rose cultivators who provided me
with the case information I needed, Jan Dobbe and Frank Ammerlaan. From the Wageningen University
& Research I would like to thank in special dr.ir. H Hengsdijk and dr.ir. A Elings.
Finally I would like to thank my roommates at the university for the help in some occasions and the nice
and appreciable time in their midst.
Groningen, May 2010
Contents
Summary................................................................................................................................................. 7
Abbreviations.......................................................................................................................................... 8
List of tables & figures ............................................................................................................................ 9
Introduction........................................................................................................................................... 11
1.
Ethiopian rift valley. ...................................................................................................................... 13
2.
Roses and how to grow them ......................................................................................................... 15
3.
Migration of rose cultivation to Ethiopia. ....................................................................................... 19
4.
Methodology ................................................................................................................................. 21
5.
Results........................................................................................................................................... 23
6.
Scenarios ....................................................................................................................................... 35
Conclusion ............................................................................................................................................ 39
Discussion............................................................................................................................................. 41
Appendix: Common pests in rose cultivation ......................................................................................... 43
Reference List ....................................................................................................................................... 44
Summary
The rose cultivation is used as a study example in this report to facilitate the understanding of the overall
differences between the cultivation of agricultural products in the Netherlands and those in warmer
countries.
The Dutch rose cultivation is on its way back. The quantities produced in the Netherlands will
presumably reduce to insignificant proportions before the year 2025. The Ethiopian rose cultivation on
the other grows on a steady rate every year. Since 2005 the rose production grew on average with about
150% per year.
The rose cultivation in Ethiopia employs a large amount of people, creating a money flow to the country
in that way. Not all revenues of the roses exported out of Ethiopia actually reach Ethiopia, but the
industry can still make up partly for the relatively large trade deficit of Ethiopia.
The Ethiopian rose requires no fossil energy in the production phase. The energy involved in the air
transport to the Netherlands is dwarfed by the energy use in the Dutch system for heating and lighting.
The cultivation in these warmer countries is often less regulated and the constituted laws are often less
maintained. The risk of local overuse of water, fertilizers and pesticides are significant and need guidance
by the authorities. The overuse of these resources can lead to the drying up of rivers and lakes,
eutrophication of surface waters or the contamination of surface waters. These effects can have serious
consequences for the living conditions of animals and civilians in lower parts of the catchment. If current
developments continue, the risk of overuse of water in Ethiopia is significant. This overuse is already
caused by other agricultural sectors that use irrigation. The rose farms could tip over the balance in some
situations.
Abbreviations
Algemene Inspectie Dienst
AID
Centraal Bureau voor de Statistiek
CBS
Central Rift Valley
CRV
Great Rift Valley
GRV
Ethiopian Producers of Horticultural Products Association
EHPEA
Integrated Pest Management
IPM
International Trade Centre
ITC
Kwantitatieve Informatie
KWIN
Millieu Effect Rapportage
MER
Personal Communication
Pers. Com.
Uitvoeringsorganisatie
UO
Wageningen University and Research
WUR
List of tables & figures
Figure 1-1: Topography of Ethiopia (mapsof.net/Ethiopia)............................................................... 13
Figure 2-1: Passion rose, stem and bud. (photobucket.com)............................................................. 15
Table 2-1: Structural aspects Dutch and Ethiopian greenhouses. ..................................................... 18
Figure 3-1: Big bud roses sold at the Dutch auction FloraHolland.................................................. 119
Figure 3-2: Small bud roses sold at the Dutch auction FloraHolland................................................ 19
Figure 5-1: Trade balance of Ethiopia (Source: IMF) ....................................................................... 24
Table 5-1: Economic indicators .......................................................................................................... 25
Table 5-2 : Energy use......................................................................................................................... 26
Table 5-3: Water & Fertilizer use in the Dutch and Ethiopian cultivation systems.......................... 29
Table 5-4: Pesticide use & application................................................................................................ 32
Figure 5-2: Sustainability on different fields evaluated. .................................................................... 32
Introduction
A large proportion of the fruit, vegetables and flowers retailed in The Netherlands is produced in other
countries and some are even cultivated on other continents. A good example of this is the production of
the Kiwi fruit in New Zealand. As a consequence of this and the wish of the consumer to know whether
these agricultural products are produced in a fair and environmentally friendly way a whole new branch
of logos has seen the light. These logos are abundant and try to differentiate between fair and unfair
production or environmentally friendly or unfriendly. Nonetheless, messages reach the Netherlands about
the negative effects of the production of our agricultural products on the population or the local
environment of the producing countries (RTL-Nieuws, 2009; NOVA, 2009).
This report makes an effort to give an impression of the differences between the cultivation systems of
several agricultural products in the Netherlands and the ones in warmer countries. For this reason the rose
was chosen to be researched in detail. This research into the cultivation of roses will give insight in the
general differences between cultivating systems in the Netherlands and those in warmer countries.
In the last decade large scale indoor floriculture is coming up in Ethiopia. Due to strong tax-incentives
(Ethiopian Foreign Department, 2006; Klaasse, 2007) Ethiopia has an even stronger attraction on
investors than other African nations. The entrepreneurs that start the rose farms in Ethiopia are primarily
foreigners, of which a substantial percentage is Dutch. These are the same Dutch rose growers that had a
hard time surviving in the Netherlands due to the competition with rose growers in Africa (Neefjes, 2009;
van den Berg, 2008; van der Schaaf, 2008) . This fast-growing intensive flower cultivating sector brings
tax-income to the Ethiopian government and employment to the inhabitants. This strong positive
economic aspect may overshadow the possible hazardous effects on the environment. Fears exist in
Ethiopia about the possible hazardous effects on nature, employees and residents in the vicinity (Amera &
Aklilu, 2008; Hengsdijk & Jansen, 2006; Obole, 2008; Zenebe, 2006). The current literature does not
describe these effects in detail and are thus to be complemented by this study. This report will elaborate in
evaluating the economical & environmental effects of the upcoming intensive floriculture in Ethiopia.
The first chapters of this report are for the reader to get familiar with the subject. In the first chapter some
geographical aspects are treated that are useful in understanding the environmental effects. In chapter two
the cultivation of roses will be treated. Chapter three then assesses the current migration of rose growers
from the Netherlands to Ethiopia.
11
12
1.
Ethiopian rift valley.
1.1 Ethiopia
Ethiopia is a land-locked country in the horn of Africa. Its furthermost eastern and western borders are at
32°59'25" and 48° East longitude respectively. The furthermost southern and northern borders are at
3°24'40" and 14°54'00" North latitude respectively. The country is bordered by Sudan, Kenya, Eritrea,
Djibouti, Somaliland, Puntland (the latter two were once part of Somalia and still lack recognition by the
rest of the world.) and what is left of Somalia.
1.2 Great Rift Valley
The Ethiopian rift valley is part of a larger structure of the Great Rift Valley that passes trough eastern
Africa and is connected to an equivalent rift in the Middle East. The rift valley is the result a tectonic
event, which is the movement of the African continental plate, diverging from the Arabic plate (Corti, G.
2009). These two diverge and leave a gap between them. This gap can be seen as a long and, sometimes
narrow, long valley that stretches from the Jordan valley in Syria, via the Sinai peninsula, into the rift
valley, which itself stretches from Ethiopia to Mozambique. The Great Rift Valley is known for its
abundant lakes. A considerably big part of these lakes is part of hydrological closed basins. These basins
are called endorheic basins. Endorheic basins have the characteristic that all the water that precipitates in
such a basin does only leave with means of evaporation or scarce underground seepage. These basins
often have terminal lakes, functioning as the endpoint of the water that precipitates in het basin. The part
of Ethiopia which is to concern of this report consists exclusively of endorheic basins, two in total. The
biggest basin of these two is the Awash basin, which consists of the full catchment of the river Awash.
The Ziway basin is smaller and it includes the lakes Ziway, Langano, Abiyata and Shala. This basin
actually consists of two basins, as lake Shala is not connected to the other lakes.
The Ethiopian rift valley has altitudes ranging from 1500 to 2500 meters. Temperatures range from 20°C
till 30°C by day and 10°C till 15°C by night (Alemayehu et al., 2006).
2.
Figure 1-1: Topography of Ethiopia (mapsof.net/Ethiopia)
13
14
2. Roses and how to grow them
This chapter will give the reader an idea of what the important factors are when cultivating roses. First of
all some technical and economic aspects of rose retailing and production are treated after which the
cultivation of the plant will be explained.
Special acknowledgements are given to the class-manual on the cultivation of roses by Ton van der Hoorn
(Hoorn 1998) and to the manual written by Preesman B.V.(Preesman BV 2008), a company specialized in
the consultancy in cut flower cultivation. These two manuals provided the information on the technical
aspects of rose cultivation in this chapter.
2.1 Technical and Economic aspects
Among the cut flowers grown in greenhouses in the Netherlands the rose has the single biggest share,
although this has decreased from 25% to 20% in the last ten years. Secondly, the amount of hectares used
for the overall cultivation of cut flowers also declined significantly. These two facts together result in a
decrease in the amount of hectares used in the Netherlands to grow roses from 932 hectares in 2000 to
532 hectares today (CBS).
The Netherlands traditionally dominated the rose cultivating industry. The migration of rose growers to
Africa is a relatively new development. Due to this history the Dutch auctions were able to build up a
dominant position on the world market. From all over the world flowers are send to the Dutch auctions to
be sold and redistributed again after. Two third of all the roses retailed worldwide is sold via auctions.
The Dutch auction FloraHolland dominates this market.
There is a distinction made in the rose growing
business between small and big roses. This is
primarily a distinction in size of the bud, but the
length of the stem is of great importance as
well. For the first, the bud size, the distinction
can be made purely with concern to rose
families and rose species. The latter, the stem
length, is a factor mostly influenced when
harvesting, depending on the physical
possibilities and the target set by the rose
grower. Common rule though is that bigger bud
size means longer stem size, both ensuring a
higher price on the market. The reader should
realize that this classification into only two
separate classes induce a wide variety within a
class itself. For a lot of species it is hard to Figure 2-1: Passion rose, stem and bud. (photobucket.com)
distinguish it as a small or a big bud rose.
2.2 Soil
There are several rose-cultivation methods in place in the world. These methods can be categorized in two
main cultivation methods: Substrate and open soil cultivation. In these two categories we can also
distinguish between heating and non-heating, and sometimes a combination of the two. This chapter will
focus on the difference between growing roses in open soil and growing them on substrate. Open soil
cultivation is the method best known among the general public, as it is associated with the rose bush in
peoples' gardens. Therefore this chapter will primarily discuss substrate cultivation, as this is presumably
the most unknown cultivation method.
15
Substrates can be made of various materials, but cocopeat and rockwool are the most common. Cocopeat
is made of waste products of a palm tree and rockwool on the other hand is made of whim stone. The big
advantage of substrate is that it is free of nematodes and other organisms living in normal soil.
Furthermore it has a known pH and known concentration of salts which can easily be adjusted to the
needs of the specific plant. For roses the best pH close to 5.5. Substrates, which normally are a bit
alkaline, therefore have to be treated with acid before cultivation can start. Normal soil is normally
slightly acid by nature, but this can differ and a grower needs to be aware of that.
In the start of production there is a big difference between open soil and substrate cultivation. In normal
soil, the root system of a wild rose bush is used as a base for cuttings. This is due to the properties of wild
roses, which are far more resistant to nematodes, fungi and other pests. Modern refined roses lost most of
their resistance to pests and are therefore not suitable to plant in open soil. On the roots of these wild rose
bushes cuttings are placed that will produce the high quality roses. In substrate, slightly bigger cuttings
than in the open soil configuration are directly placed in to the substrate. These cuttings are then allowed
to evolve and turn into a rose bush. The roots of these rose bushes are normally slightly underdeveloped
and concentrated on the places where the drippers release their water.
2.3 Climate
For the production of high quality and high amounts of roses climate control is absolutely necessary.
Roses can be quite forgiving plants when high quality and production rate is not that important. For a
high production rate a stable climate is necessary though. In countries like the Netherlands heating is
often needed to ensure a nearly constant production all year round by keeping the greenhouse at a day
temperature around 20 °C every day. In winter extra light is needed, as the amount of day hours decrease
as well as the intensity of the sunlight. These two measures ensure the use of big quantities of natural gas
(however, most rose-growers use an aggregate to produce the power for the lighting and use the rest heat
to heat up the greenhouse.). The use of an aggregate (called a Power-Heat combination by the growers,
Warmte-Kracht Koppeling in Dutch -WKK) has the extra advantage that it can bring in an additional
amount of CO2 in the greenhouse.
Roses prefer a day temperature between 20 and 25 °C and a night temperature of around 15 to 18 °C. In
the Dutch summer, these temperatures are certainly not uncommon, making the Netherlands in the
summer a suitable production location. In some models it is preferable to let the greenhouse cool down
during winter, cutting on the expenses made on natural gas. In this period the roses produce few to no
buds at all. This can mean that a rose bush with a life cycle of 3 or 4 years (Depending on the type of
roses in use) is not used half of its productive life. These figures hold for the soil cultivation as for the
substrate cultivation as well.
The temperature around roots may never come above 25°C, as it damages the roots and promotes the
growth of fungi. This means that growers sometimes have to take measures to ensure that their irrigation
water does not get to that temperature. Temperature differences in the plant canopy should be avoided.
This leads to some apparent strange situations as it can be advised to heat under the plants when the sun is
shining intensely. This is explained in the following way: The sun heats up the top canopy of the plants
the most, creating a temperature difference in the plant canopy, which is undesired. By heating under the
plants the temperature gradient is diminished.
2.4 Water and fertilizers
Roses are water loving plants, despite of their sensitiveness to fungi that thrive in humid circumstances.
The best way to water roses is by drip irrigation. This gives the advantage of knowing how much each
plant receives and that every plant actually gets the same amount. It is important for roses in open soil
cultivation as well as for roses in substrate that the roots are not in a constant state of humidity, but rather
have frequent access to air. This has the following reasons: Roots need oxygen for the active uptake of
16
nutrients and secondly, roots of roses are vulnerable to fungi when the humidity is constantly on a high
level. This has as consequence that substrate cultivation is preferable in the cultivation of roses. Substrate
is more open and thus lets the water run trough quickly. The rose plant can absorb the water and nutrients
it needs and the remaining drain water can be collected under the substrate layer.
The collection and the subsequent measurement of the amount of drain water is essential. To prevent
salinization of the substrate the measured drain percentage of the initial amount of water should remain
above 35%. Yet, above 50% of drain can indicate that too much water is given to the plants, making the
substrate possibly too humid. Additionally, growers measure the EC (Electrical Conductivity) value of
their drain water, as it indicates how many nutrients the plants are extracting from the water. The water
given to plants should have an EC value of 1.2 to 1.4 S m-1. The drain water should have an EC value
between 1.6 and 1.8 S m-1 optimally, as the roses relatively absorb more water then nutrients. This is of
concern in open soil too, but some of the parameters mentioned above cannot be measured in the case of
open soil cultivation. In open soil one can measure the salinity of the soil by taking samples of the soil
itself and sending this to a lab for analysis. This is, however, a rather coarse method to determine if the
given water has the right EC value and pH compared to measuring these values in the drain water of
substrate.
2.5 Pests & Diseases
One can divide the natural hazards that threaten the cultivation of roses into fungi and insects. In the
Netherlands the three dominant hazards are mildew, thrips and red spider mites. Rose growers use
pesticides and Sulphur against these pests. There are no strong reasons to assume that the main pest
problems in Ethiopia will be very different from those in the Netherlands, although the expectations of
experts in the field is that the pest problems are bigger. A big difference between the Netherlands and
Ethiopia is the high humidity that is present in the rainy season in Ethiopia. The high humidity can
stimulate the growth of fungi on the roots and sometimes on the plants itself.
The amount of pesticides used depends on whether a farmer is using Integrated Pest Control (IPC) or not.
IPC incorporates the use of natural enemies of trips and mites that are seen as a danger to the crop. These
predatory insects are kept in a colony in the greenhouse, but need a certain amount of prey to stay alive.
This has as consequence that bringing the amount of harmful insects to zero is not an option, as the
predatory insects would die too. Using IPC also means that a lot of pesticides cannot be used, as they
would kill the predatory insects too. Especially the amount of Sulphur is lowered. Sulphur is commonly
used to combat mildew, but is also deadly for most of the predatory insects. Instead of Sulfur growers
have to use synthetic chemicals to combat mildew. The reader can find information about the three most
common pests in rose cultivation in the appendix.
2.6 Situation and structural aspects
Ethiopian greenhouses are situated in the Great Rift Valley (GRV) (Hengsdijk & Jansen, 2006; van Os,
2009; Westenbrink, personal communication 2010). The climate in the GRV has in all aspects few
extremes, making it suitable for controlled growing of crops. The Netherlands on the other hand,
experiences relatively cold winters, making heating a necessity during winter. This, together with lighting
during the winter, brings high costs and ensures a greater amount of primary energy use per rose.
Depending on the climate and the demands on the turnover per square meter the grower may choose to
build a sophisticated glass greenhouse or a simple plastic one. The glass has a better transmission in the
visible range of the electromagnetic spectrum and is to be preferred in the case of light shortage. Glass
needs a strong framework to keep it in place, making this option far more expensive than the plastic
alternative. A warm climate (good cultivation conditions), as in Ethiopia and Kenya, come hand in hand
with cheap labor and cheap soil. This means that turnover per square meter is not as important as it is in
countries with cold climates, high labor costs and expensive soil like the Netherlands. The minimum
turnover per square meter required for a specific Dutch rose grower is around 100 Euro (Dobbe, pers.
17
com. 2009; Vermeulen, 2008). One should take into account that most Dutch growers need even higher
turnovers to survive, as they cultivate on even more expensive soil in other parts of the Netherlands. The
minimum turnover needed in Kenya and Ethiopia is estim ated to be around 30 Euro per square meter
(Dobbe J., Ammerlaan F.). The greenhouses in Ethiopia have a far lower capital intensity and have a
lower durability. The plastic made greenhouses are standing on open soil. These greenhouses inhibit less
mechanization and technology. They produce their crops on open soil, do not feed their plants with CO2
and do not have a way to check the EC value of the drain water as the substrate growers have. These
aspects have an impact on the qualitative outcome of their crop.
The market wants flowers of very high quality for low prices. This leads, primarily in the Dutch system,
to several optimizations. As investment costs are considerably higher in the Netherlands, as well as labor
and energy costs, there is a big desire to have as much turnover per square meter as possible. Labor is a
quantity that is mostly affected by the production, so it could be handled as variable production costs.
Energy on the other hand, in the form of lighting and heating, is a fixed number per square meter.
Together with high investment costs these two lead to a strong optimization of the turnover per square
meter.
Table 2-1: Structural aspects Dutch and Ethiopian greenhouses.
Value
Main material greenhouse
Bottom greenhouse
Cultivation soil
Heating
Lighting
Altitude
Average yearly max. temperature
Average yearly min. temperature
18
Dutch system
Glass & steel
Concrete
Substrate
Yes
Yes
0-50 m
30 °C
-5 °C
Ethiopian system
Plastic & steel
Open soil
Open soil
No
No
1500-2000 m
35 °C
10 °C
3. Migration of rose cultivation to Ethiopia.
From the moment that the first rose cultivating farm started production in Ethiopia in 1999, the amount of
roses exported to the Netherlands has increased exponentially. Different types of roses are produced and
price differentiates heavily between them. Ethiopia produces both small and big bud roses. Most of the
flowers from both the Netherlands and Ethiopia are sold at the Dutch auctions, of which the one in
Aalsmeer is the biggest. The number of roses that is directly sold to the buyers is at least twice as small as
the amount of the roses that is sold at the auction. (FloraHolland, 2010; Klaasse, 2008). This is confirmed
by experts and rose growers. The price at the auction will thus be considered the market price in this
report.
Figure 3-1: Big bud roses sold at the Dutch auction FloraHolland.
Figure 3-2: Small bud roses sold at the Dutch auction FloraHolland.
19
3.1 (Dis-)Advantages
Ethiopia offers several advantages for the cultivation of roses compared to the Netherlands. The most
obvious one is the climate. The Ethiopian greenhouses are situated in the Great Rift Valley (GRV (XX)).
The climate in the GRV has in all aspects few extremes, making it suitable for controlled growing of
crops. The Netherlands on the other hand, experiences relatively cold winters, making heating a necessity
during winter. Heating together with lighting ensures high costs during winter. The option to stop
production during winter is practiced here and there, but seems to be judged as a lesser option by the
majority of the growers.
The second big advantage of Ethiopia when compared the Netherlands are the labor costs. These are
negligible in Ethiopia when compared to the Netherlands in terms of euro per hour. Although the amount
of working hours per square meter is several times higher in Ethiopia, the contribution of labor costs to
the total production costs is far lower in Ethiopia, both in terms of euro's as in percentages (Ammerlaan,
personal communication, 2010; Sprout, 2008; Vermeulen, 2008).
A disadvantage though is that these roses have to be transported to the Netherlands before they can be
sold. These additional cost makes up half of the total costs for the rose farms in Ethiopia. The bigger the
rose is, the more it will weigh. That means that the transportation costs of small bud roses are far smaller
than the transportation costs for the big bud roses. Due to this fact, producing small bud roses is
economically viable in Ethiopia. The amount of small bud roses produced in Ethiopia is more or less the
same as the amount of big bud roses.
3.2 Prices in the Netherlands
The fortune for the Dutch system is that their big bud roses are still higher valued then the Ethiopian ones.
The reason for this difference is not very clear. This difference in price seems to be only present at the
auctions though, as the price of roses in supermarkets and at the florist do not differ significantly. More
important, rose origin seems to be of no importance when it is sold to a customer (RTL Nieuws, 2009).
This indicates that the prices will tend to grow towards each other. Quantity as well as quality of the roses
produced in Ethiopia (and other African countries) is increasing (Ammerlaan 2010, Dobbe 2010), pushing
the Dutch rose growers out of business.
20
4.
Methodology
The methodology used in this research is similar to that used in a research by Van der Velden, Janse,
Kaarsemaker & Maaswinkel (2004) in which the Spanish tomato production was compared to the Dutch
tomato production. In this research three main sources of information were used; literature, personal
measurements and interviews or personal communication. As the subject of this research is on great
distance from the location of the researcher, personal measurements and observations were not possible.
The evaluation of the research question was, as in other comparisons of sustainability of the production of
agricultural products in different countries by Van der Velden et al. (2004) and Verhaegh (1996),
facilitated by assessing the impact of separate factors. In this research these factors are: energy, pesticides
and fertilizers. Two more factors are added to this list, namely water and economy. The reason for this is
that sustainability in Ethiopia concerns more than nature-preserving or environment-preserving aspects.
Economic development is extremely important for a country like Ethiopia, which still is one of the
poorest countries in the world. Secondly, one should realize that Ethiopia is partly a very arid country,
making water scarce in large parts of the country.
The research process can subsequently be divided in three stages: Reconnaissance, data accumulation and
evaluation. These stages are not separated temporally from each other in the sense that one stage starts the
day after the other has finished. These stages flow into each other and this process even starts on different
moments for separate subjects in the research. As a start a literature survey on published data was
conducted acquire knowledge what was already published on the rose cultivation in Ethiopia.
4.1 First stage: reconnaissance
After an extensive survey trough scientific journals and the internet it became clear that not much had
been published jet on this subject. The focus was thus relayed to finding any published work on the
environmental effects of agriculture in the Great Rift Valley (GRV). In this first stage the name of
Wageningen University and Research (WUR) appeared frequently. It became clear that the university of
Wageningen has been and still is involved in a number of projects in Ethiopia. These activities are joint
research programs with local universities, but proper research and consultancy in collaboration with or for
solely farms or other institutions also exist. It became clear that a substantial amount of knowledge about
the situation in the Ethiopian rift valley was present at the WUR.
For this reason contact was sought with Huib Hengsdijk, one the most frequently appearing authors in
relation to the rift valley and WUR. Huib Hengsdijk focused on horticultural development and general
environmental aspects of the Central Ethiopian rift Valley (CRV). The horticultural development was in
cooperation with or commissioned by the Dutch ministry of agriculture, the Dutch embassy in Ethiopia
and the Ethiopian government. From him an idea of the state of the floriculture in Ethiopia was obtained.
Secondly more literature and names of people working in this field were obtained from Huib Hengsdijk
that would lead to more interviews and insights. Besides Huib Hengsdijk, contact was sought with
companies or organizations active in this field.
Knowledge was obtained about from a class manual on the cultivation of roses (van der Hoorn, 1998) and
another manual written by a company specialized in consultancy in the cultivation of cut flowers
(Preesman, 2010). From these two manuals, combined with public information on the internet and
personal communication with a rose farmer (Dobbe, pers. com. 2010), an impression was formed about
what rose cultivation is.
21
4.2 Second stage: Data accumulation
When a good impression was obtained from the interviews and the literature survey, the researcher could
start to acquire data from different sources. These sources include data sheets received from FloraHolland
and the International Trade Centre (ITC), a number of catalogs and two cases. One in the Netherlands and
one in Ethiopia. For the Dutch case, an interview was possible to assess the topic.
A visit was paid to a rose growing company, which is situated in Klazienaveen, in the North of the
Netherlands (Dobbe, personal communication, 2009). comparable list of questions was later sent to a
Dutch rose grower in Ethiopia (Ammerlaan, personal communication, 2010). The data obtained from the
two cases was compared to each other and related to information obtained from other sources. In this
process, the data received from FloraHolland (2010), CBS (2010) and the data obtained from the
Kwantitatieve Informatie Glastuinbouw (Vermeulen, 2008) were specifically important.
Reports prepared by the Dutch controlling agency for agriculture, the Algemene Inspectie Dienst (AID),
were obtained to gather information about the status of the pesticide use in the Dutch greenhouses.
Explicit reports that assess the situation in Ethiopia are not available. Therefore specialists in the fields of
Integrated Pest Management (IPM) and pesticides were asked to give their view on the situation in
Ethiopia. Some of these experts have been working in Ethiopia with relation to IPM.
4.3 Third stage: Evaluation
When all the available data was assembled, analysis followed. Different data sets were rescaled and
restructured to a desired template. In this process the data from different sources were verified to ensure
their reliability. When contradictions were encountered more references were sought. Controlling
agencies present in the countries of concern and certifying organizations were asked about the compliance
of the rose growing farms to the rules. Data coming from the ITC, CBS and FloraHolland were analyzed
and compared with each other and with the statements made by experts and rose farm owners.
For the indicators, as in Verhaegh (1996) and Van der Velden et al. (2004), primary energy in Joules is
taken as an indicator for energy use. This energy is calculated per rose stem. In the case of water liters per
stem was used and in the case of fertilizers and pesticides the amount of used dry material in kg per stem
is used. Land use, geographical situation, money flows and social conditions are also taken into account.
22
5.
Results
In this chapter the results that have been obtained during the research will be listed and explained. The
results have been classified into four different categories. These categories are:
•
•
•
•
Economic & Social aspects
Energy
Water & Fertilizers
Pesticides
These categories are first treated apart from each other and eventually the results are assessed together.
Some data is listed in tables. Of this data the origin and associated references are to be found in the text
that is either above or under the table. In the text the figures are explained and assessed. The tables have
an illustrative purpose, listing the facts that can be found in the text.
5.1 Economic & Social aspects
5.1.1 The Dutch system.
The market wants flowers of very high quality for low prices. This leads, primarily in the Dutch system,
to several optimizations. As investment costs are high in the Netherlands, as well as labor and energy
costs, there is a big desire to have as much turnover per square meter as possible. The energy use in the
form of lighting and heating is a fixed quantity per square meter. Together with high investments per
square meter these two lead to a strong optimization of the turnover per square meter.
Dutch roses are still higher valued then the Ethiopian ones. The reason for this higher price is not totally
clear. According to a Dutch rose grower in Ethiopia (Ammerlaan, pers. com. 2010) this cause is threefold;
quality, under-appreciation and sometimes difference in rose types. The name that the Dutch rose
cultivating industry has built up in the past helps it to stay alive. Dutch roses are still known for their
quality and lasting vase-life. This difference in price seems to be only present at the auctions though, as
the prices in supermarkets and at the florist do not differ significantly. More important, rose origin seems
to be of no importance to a customer (RTL Nieuws, 2009). This indicates that the prices will tend to move
towards each other. Quantity as well as quality of roses produced in Ethiopia (and other African
countries) are becoming higher, pushing the Dutch rose growers out of business. Quality is improving as
production managers are learning and gaining experience.
When subtracting the average production costs and the labor costs from the turnover per rose one is left
with nothing to sometimes negative results per rose for a Dutch rose growing company. With no revenues
for the rose growing companies there is no room for investments on their side. Reducing company size is
bad for business too as some costs stay the same while the revenues go down but investments on the other
hand are not affordable. Lower prices at the auction (thus in general) would be bad news for the Dutch
rose growers.
5.1.2 The Ethiopian system.
Rose growers in Ethiopia have several advantages when compared to rose growers in the Netherlands.
The absence of energy input and lower labor costs are the most important. These reasons ensure a very
low production cost per rose. A disadvantage though is that these roses have to be transported to the
Netherlands before they can be sold. This additional cost makes up half of the total costs for the rose
farms in Ethiopia. Producing small bud roses is economically viable in Ethiopia. The amount of small
bud roses is more or less the same as the amount of big bud roses. The reader must keep in mind that
there are species between big and small bud classifications but still have to be places into one of the two
classifications by the auction. This has an impact on the average amount of flowers per square meter, as
23
the small bud roses can be produced in higher densities. The average amount of roses per square meter
listed in table 5-1 is thus also an average between small and big bud roses.
The warm climate (Good cultivation conditions in general) in Ethiopia and Kenya, come hand in hand
with cheap labor and cheap soil. This means that turnover per square meter is not as important as it is in
countries with cold climates, high labor costs and expensive soil like the Netherlands. The minimum
turnover per square meter required for a specific Dutch rose grower (Dobbe, pers. com. 2009;
Vermeulen, 2008) is around 100 Euro. One should take into account that most Dutch growers need even
higher turnovers to survive, as they cultivate on even more expensive soil in other parts of the
Netherlands. The minimum turnover needed in Kenya and Ethiopia is estimated to be around 30 Euro per
square meter (Dobbe, pers. com. 2010; Ammerlaan, 2010).
The greenhouses in Ethiopia have a far lower capital intensity and have a lower durability. The plastic
greenhouses are standing on open soil. These greenhouses inhibit less mechanization and technology.
The growers produce their crops on open soil, do not feed their plants with CO2 and do not have a way to
check the EC value of the drain water as the substrate growers have. This has an impact on the qualitative
outcome of their crop.
5.1.3 Ethiopian economic & social aspects
As was the case with rose production in Kenya, there is a tendency to point at the low wages paid in
Ethiopia to the local employees (Ammerlaan, pers. com. 2010; RTL Nieuws, 2009; Sprout, 2008). This
criticism has as central point that the rose growers make profit while their employees get little money for
their efforts. This criticism is especially strong from the countries where the growers originate. This can
not to be attributed solely to entrepreneurs and employers in Ethiopia. This does not mean that they
should not feel any moral obligation to do anything about it.
The question whether the rose growing industry is good for Ethiopia in an economic sense cannot be
assessed by taking only the wage into account. The trade balance and the overall condition of the
Ethiopian economy are extremely important in this question as well. The trade balance of Ethiopia is
extremely negative (ITC, 2010), importing nearly 8 billion Euros versus a mere 1.5 billion Euros of
export. This has been the case Ethiopia regained independence in 1944, with exception of a few years.
In the last few years this deficit has grown strongly. For comparison, the total size of the Ethiopian
economy was around 20 billion Euro's in 2008 (World Bank, 2010), the trade deficit was nearly 5 billion
Euros in the same year. This
trade deficit is partly balanced by
a money flow in the form of aid
from wealthy nations. Ethiopia
received an amount of more than
2.5 billion Euros in 2008 in the
form of aid (OECD-DAC, 2010).
The rest of the trade deficit is
compensated by Foreign Direct
Investment (FDI) and by loans.
These loans have increased in
size in the last years (World
Bank, 2010). To develop to and
become a middle class income
country defined by the standards
of the World Bank, Ethiopia
needs to rise its export and Figure 5-1: Trade balance of Ethiopia (Source: IMF)
subsequently lower the import,
24
which is costing the country a lot of money. The new upcoming rose growing industry creates export
value and is in that sense good for Ethiopia. Besides the export value, the industry creates employment for
tens of thousands of employees. More local employment creates more a bigger and stronger local market
where other products can also be sold. Important condition here is that these products have to be produced
in Ethiopia, or else the trade balance will not improve. Other factors are of importance too in this
discussion. Ethiopia should implement more regulations to ensure a more stable national coin, as the
inflation rates are extremely high in the past years. Inflation was 25% and 36% in 2008 and 2009
respectively (IMF, 2010). Average GDP per capita in Ethiopia is around 350-400 US$ (IMF, 2009; World
Bank, 2009). This is more or less 1.5 US$ per workday (6 days a week work plus 2 or 3 free days a month
extra.).
The minimum wage used by a the interviewed Dutch rose grower (Ammerlaan, pers. com. 2010) is about
2 US$. This is higher than the average wage and is paid for unskilled labor. Knowing this, it is not so
strange that working for rose growers is popular in Ethiopia, especially under the unschooled population.
It is believed that these wages do not differ among other foreign employers. The wages will have to grow
along with the economy though, if the payments are to keep on being a positive effect on the economy.
The value of the flowers originating from Ethiopia sold at the Dutch auctions higher than the value of all
the exported cut flowers of Ethiopia (FloraHolland, 2010; ITC, 2010). This on itself is a very strange
phenomenon, even stranger considering the fact that presumably only two third of the roses exported from
Ethiopia has the Dutch auction as destination. A theory is that foreign rose growing companies use a
holding in the Netherlands where the flowers are sold for a constant and fairly low price (often 10 cents
per rose). These holdings then sell the flowers at the auctions where a (higher) variable price exists
(Neefjes, 2009). This system ensures a steady flow of money to Ethiopia, but keeps the (variable)
revenues in the Netherlands. In itself this is a legal system, but whether it is fair remains to be seen. A part
of the FDI in Ethiopia originates from loans of Dutch banks or from banks in other nations. This means
that part of the revenues has to be used in these countries to pay off the loans. The organization
responsible for the FDI (In the Netherlands for example) is obviously also entitled to profit, but the
question remains whether Ethiopia should receive a bigger part of this cake.
Table 5-1: Economic indicators
Value
Average price at
Big bud roses
auction in 2009
Small bud roses
Variable production costs
(Labor excluded)
Dutch system
0,31
0,093
0,166
Ethiopian system
0,149
0,1
0,044
Unit
€ / flower
Transportation costs
Primary investment costs
Production rate
Turnover
Labor price
Labor quantity
Total labor costs
0,0055
75 - 100
250-300
80-100
30
1,7
0,165
0,06
25
250-260
30-35
0,5
8*
0,016
€ / flower
€ / m2
Flowers / m2
€ / m2 / year
€ / person-hour
Hours / m2 / year
€ / flower
€ / flower
For the data listed in table 5-1, figures from the KWIN Glastuinbouw (Vermeulen, 2008), statistics from
CBS (CBS, 2010) and FloraHolland (FloraHolland, 2010) and personal communication with rose growers
(Ammerlaan, pers. com. 2010; Dobbe, pers. com. 2010) were used.
25
5.2 Energy
The energy needed to produce roses in the Netherlands is about 25 times higher than the energy involved
in transporting Ethiopian roses to the Netherlands. The energy use is 19.25 and 0.8 MJ of primary energy
per rose for the Dutch and Ethiopian rose respectively.
Table 5-2 : Energy use
Form of energy use Dutch system
(With WKK)
Ethiopian system
Unit
Heating
Lighting
Air transport
6.72*
12.53*
0
0
0
0.8
MJ of primary energy per flower
MJ of primary energy per flower
MJ of primary energy per flower
Total
19.25
0.8
MJ of primary energy per flower
*Error! Reference source not found. uses a yield of 302.5 flowers per m2 for the Dutch system
(Vermeulen, 2008).
5.2.1 Calculation of Dutch heating and lighting energy costs
The Heat-Power combination in the Dutch system combusts 101.7 m3 of natural gas per m2 per year (
Vermeulen, 2008). This is equivalent to 3128.6 MJ m-2 y-1. Vermeulen (2008) claims electricity
production efficiency of an average Heat-Power combination is 37.6%. The rest heat is accounted for the
heating of the greenhouse. This makes the electricity production seem more efficient than it actually is.
This is allowed this due to the fact that the total energy consumption is still attributed to the same system.
The now calculated energy that is released in the combustion of natural gas must be multiplied by a
certain factor (called the ERE factor). This factor takes the energy costs to harvest and transport the
primary energy carrier to the location of combustion into account. For the case of natural gas this is 1.01
(Wilting 1996). We now arrive at a total primary energy consumption in the form of natural gas by a
Dutch greenhouse of 3250.8 MJ m-2 y-1. 37.5% of this energy is used for lighting and the rest is used for
heating.
The electricity use of the Dutch system is in total 632,5 kWh m-2 y-1. This is mostly supplied by the
WKK and the rest is supplied by the grid. The grid supplies 288 kWh m-2 y-1. This is equivalent to 1037
MJ m-2 y-1. This amount needs to be divided by the efficiency of the Dutch electricity production. This
efficiency is estimated to be 44% in 2009 (IEA, 2009). Finally, we consider the so called ERE values.
These are 1.01 and 1.25 for natural gas and coal respectively (Wilting, 1996). At the moment roughly
60% of the Dutch electricity is made from natural gas, 30% coal and 10% other sources. For the 10% of
combined sources (Nuclear, biofuels & renewables) an average ERE value of 1.1 is taken. This leads to
an average ERE value of 1.09. This means that the primary energy used to supply the greenhouse with
288 kWh m-2 y-1 costs about 2571.3 MJ m-2 y-1. Dividing the total amount of energy used per square
meter by the amount of roses per square meter one finds that the Dutch systems uses nearly 20 MJ per
rose.
5.2.2 Transport of Ethiopian roses
The primary energy costs of the air transport of the Ethiopian flowers are still far lower than the combined
energy costs for heating and lighting in the Dutch system. For the primary energy for the transportation
different numbers and units arise in the literature (Komor 1995, Wee et. al. 1997, Essen et. al. 2003,
Peeters et. al. 2005). The highest is taken to function as the primary energy in MJ ton-1 km-1. By
combining the energy per kilogram with the average weight of a rose according to Morisot et al. (1998) of
11.5 grams per rose we get the primary energy per rose. This weight will be lower of course if the stem of
26
the rose does not have the maximal length. This can be up to 40% lower if the grower cuts off a part of
the stem. In this way we are assured of a safe upper limit. We find that the energy involved in transporting
the Ethiopian roses is near to 1 MJ per rose.
The primary energy that is involved in the transportation by truck over about 200 km in both situations is
about 2 orders of magnitude smaller than the other energy consuming processes listed above. This
brought the researcher to the conclusion that listing the amount of primary energy used in the
transportation by road makes no sense at all and can thus be left out of the evaluation. The energy needed
to build up the greenhouses has not been taken into account here. The heating and transportation cost in
this field are traditionally orders of magnitude higher than the energy needed to build up the greenhouses.
5.2.3 Comparison to tomatoes.
An informed reader may notice that the difference in energy use of the two systems is significantly more
than in the case of tomatoes or other vegetables, when a Dutch system is compared with one originating
from a warmer country. The reason for this difference is twofold. The first and most important reason is
that vegetables growers in the Netherlands stop production in winter. This reduces their own primary
energy use by more or less by 60% (Vermeulen, 2008). The second reason is the fact that the energy that
is used to fly a specific object from one place to another is linear with its weight. As a vegetable such as a
tomato weighs 8 to 10 times more than a rose, the energy used to fly it to the Netherlands is thus also 8 to
10 times higher. Taking these two factors into account one can end up with a marginal difference in
energy use or the same energy use in a Dutch system and a foreign system that has to bring the crops to
the Netherlands by plane.
5.3 Water & Fertilizers
5.3.1 Water use
In both systems the water use is higher than the annual amount of precipitation. This is of no harm in the
Netherlands. In the Netherlands, the rose growers use 30% more water than the annual precipitation,
namely 1140 liters per hectare (Dobbe, pers. com. 2010) compared to an annual rainfall of 700 mm
(KNMI, 2010). Being the end point of two major European rivers, the Netherlands receives and
sometimes endures large amounts of water. Beside of the incoming water, the evaporation in the
Netherlands is lower than the precipitation received (KNMI, 2010). This leads to the conclusion that a
slightly higher water use per hectare of greenhouse is of no concern whatsoever in the Dutch case.
In the Ethiopian case however, there is a slight risk of local overuse. Farmers should be able to lower their
water use if they would collect and store rain water (van Os, 2009). Local observations (Morris, 2006; van
Os, 2009) confirm that some of the rose growing farms in Ethiopia use collected rain water, but this
seems to be a minority. Most of the farms use ground water and some use surface water, when available.
Surface water in the form of rivers has a downside though, as the water can be extremely dirty in the rainy
season. This leads to only partial use of rivers. Lakes on the other hand can be used all year long to
extract water. This is also the case at the largest floriculture complex of the country, near lake Ziway, the
Sher complex. Irrigation water is subtracted from the lake and precipitation water is canalled back into the
lake. Company expectations were that this complex would consist of 450 hectares in 2010. (Hengsdijk &
Jansen, 2006; Kassa, 2008; van den Berg, 2008). For these 450 hectares an amount of 11.5 million m3 of
water is extracted from Lake Ziway (Hengsdijk & Jansen, 2006; van Os, 2009). The inflow (rivers and
precipitation) in to Lake Ziway is estimated around a billion cubic meters a year. Most of this water
evaporates and only a minor part finds its way out trough a runoff from the lake in the form of the river
Bulbula. This runoff was reported to be around 110 million cubic meters per year a few decades ago
(Hengsdijk & Jansen, 2006).
The Bulbula flows into Lake Abijata. This lake is a terminal lake, the endpoint in a so called endorheic
basin. As mentioned before, in an endorheic basin all the water that precipitates only leaves with means of
27
evaporation or scarce underground seepage. The runoff of the Bulbula river has declined in the last
decades, the current runoff is substantially lower compared to some decades ago. This is due to extraction
of irrigation water from the rivers that run into lake Ziway (Meki and Ketar rivers), less rainfall, water
extraction from lake Ziway itself and extraction of irrigation water from the river Bulbula. The extraction
of water for irrigation purposes is still several times higher than the water use of the Sherr complex
(Hengsdijk & Jansen, 2006). The irrigation is primarily for horticulture companies, but there are a lot of
smallholders too that use irrigation water. In both cases furrow irrigation is used, which is known for its
inefficiencies. The biggest factor though is the size of the irrigated surface. This area is mentioned to be
more or less 8000 ha (Hengsdijk & Jansen, 2006). The decline of the amount of water going through the
Bulbula (And the subsequent drop in the water level of lake Abijata, the terminal lake) river cannot be
completely attributed to the Sherr complex. Even considering the foreseen water use of the Sher complex
in 2010, it would still be a minor factor. However, this does not mean that it is not partly responsible for
this decline, neither that is unaffected by the consequences. With a decreasing runoff the salinity of lake
Ziway will rise, making the water less and less appropriate for the use as irrigation water. A worst case
scenario here is the possible dry-up of the river Bulbula, turning lake Ziway into a terminal lake. This will
have a huge impact on the way it can serve as a natural resource for humans, but it will also have a
devastating impact on the flora and fauna that now thrive on the fresh water of lake Ziway. It is in the
interest of the rose farms, local inhabitants and the local governments to avoid this.
The rest of the rose growing farms, around 500 to 600 hectares, are located in the Awash river catchment
(Elings, pers. com. 2010; Hensdijk, pers. com. 2010; Kassa, 2008; Westenbrink, pers. com. 2010). This
catchment comprises the whole area of the Great Rift Valley north of the Central Rift Valley. The Awash
river has its source west of Addis Abeba, and flows through a series of connected lakes to the lake Abhe.
Lake Abhe is the final lake in another endorheic basin, just like lake Abijata, but far larger. One of the
lakes that are connected to each other by the Awash river is lake Gelila (also called lake Koka). This lake
is the product of the Koka dam, build in 1960. This lake is heavily contaminated these days (Zinabu &
Pearce, 2003). This is due to its position, as it receives the affluence of the Awash river coming from
Addis Abeba, and the industry that has risen around the lake. This industry primarily consists of a leather
tanning factory and several horti- and floricultural farms around the lake. The rose farms in this basin
primarily use ground water for irrigation. This has its influences on the water table in the soil of course,
but the effects are not completely understood.
28
5.3.2 Fertilizer use
One can state that there is no fertilizer loss in the Dutch system, as all the water is reused. This is different
in the Ethiopian system, as there is no reuse of drain water. This drain water seeps into the underground
and either finds its way into nearby lakes or rivers or ends up in the deeper groundwater. This brings
along the of eutrophication of surface waters. Eutrophication of surface waters normally leads to the
clearly visible explosive grow of algae and/or bacteria. There are reports that this is the case at the Koka
reservoir (Zinabu & Pearce, 2003), but it is not clear who is responsible for this. Clear is though that
eutrophication is a serious danger to the central Ethiopian basins, as they do not discharge a surplus of
fertilizers into the oceans. In these endorheic basins the fertilizers accumulate in the lakes, especially in
the terminal lakes. This can, on the long run, make the water toxic to fish and other animals. Besides this,
the water may become unusable for irrigation, which is a problem for the agricultural industries that use
the water for irrigation themselves. No reports have been found suggesting rose producing companies in
Ethiopia being responsible at the moment for visible eutrophication of surface waters. The companies
should be aware of the danger, as the consequences are catastrophic for the environment as well as for the
companies themselves. Using Table 5-3 one can calculated that the Sherr complex in Ziway presumably
uses 500 to 800 tons of fertilizers every year. Further research is needed to evaluate the effects of this
fertilizer use on the local environment.
Table 5-3: Water & Fertilizer use in the Dutch and Ethiopian cultivation systems.
Resource use
Direct irrigation
Origin of irrigation water
Dutch system
~3-4
Ground water /
surface water
Ethiopian system
~6
Ground water /
surface water
Unit
Liters per m2 per day
N.A.
Drain water (re-circulated)
Runoff direction
Use of fertilizers
CO2 fertilizing
35%
Recirculation
0.5-0.7
Yes
N.A.
Ground water
0.7-1
No
N.A.
N.A.
Grams per rose
N.A.
Data retrieved from reports (Hengsdijk & Jansen, 2006; Van Os, 2009) indicate a higher water use in the
Ethiopian system, also on the location of the biggest greenhouse complex of the country (The Shercomplex). These reports suggest 6 to 7 liters per square meter per day of irrigated water. This is in line
with the statement of the meteorologist Klaassen (Pers. com., 2010) that the evotranspiration may well be
the same in Dutch and Ethiopian greenhouses. In that way of reasoning one would take the net Dutch
water use (3-4 liters a day) and account a total of 35% of drain in to the subsoil in the Ethiopian water
giving system, bringing the amount of water given to the plants on about 6-7 liters, which concurs with
the number stated in suggested above. The amount of fertilizers in the Dutch system has been established
at 0.5 to 0.7 grams of fertilizer per rose stem. This has been calculated using data from the Uitvoerings
Organisatie (UO, 2010) and the cultivation guide of Preesman BV (Preesman, 2010). The amount in the
Ethiopian system is calculated using the drain water percentage used in the calculation of the water use.
This, of course, relies on the assumption that in both systems the grower uses the same EC-value (And
thus the amount of fertilizers) in the irrigated water. This assumption may be justified by the fact that the
EC-value used by farmers is primarily dependent on what is best for the rose bush and less on other
factors.
29
5.4 Pesticides
Pesticide use is traditionally high in the rose cultivating industry. Roses are used as decoration and are
subject to extremely high standards. Roses are expected to be free of spots and small insects when
retailed, even on the leaves. The use of pesticides in the cultivation of other greenhouses crops is lower
due to the fact that these crops are either eaten (Vegetables & fruits) or the standards are lower (Potted
plants and other cut flowers). Beside of the high standards, roses are also very sensitive to pests compared
with other cut flowers. Spots and discolorations are easily created.
5.4.1 Pesticide use in the Netherlands
Dutch rose growers are more restricted in their choice of weapon versus pests than their Ethiopian
colleagues. These restrictions come from the Dutch government which restricts the number of pesticide
types that are to be used in the crop protection programs. A typical rose grower in the Netherlands in 2008
uses 80 to 90 kg of dry pesticide material per hectare to combat pests (CBS, 2010; Dobbe, pers. com.
2010), Including the use of Sulphur. The use of pesticides without taking Sulphur into account is 50-60 kg
per hectare (CBS, 2010; UO, 2010). In response to the government restrictions, personal motivations and
sometimes to be able to keep up a good name towards the market a big share of the rose growing
companies use Integrated Pest Control (IPC). This lowers the amount of pesticides used. As a
consequence of the fact that more than 50% of the rose growing companies use IPC (MPS, 2010), the
amount of pesticides that are used in the Netherlands lowered in the late nineties en the first years of the
current century. Since the new regulations in 2005 the amount of pesticides used has increased again
(CBS, 2010; UO, 2010). This can partly be explained by the fact that farmers need to use more of less
effective chemicals to reach an acceptable level of pest management. Since 2003 the sustainability
indicators score of the Dutch rose grower (Energy, pesticides & fertilizers) has lowered significantly (UO,
2010). For this reason it is expected that the growing competence from abroad also presses the Dutch rose
growers to use more pesticides.
Several methods are used to check whether the farmers are complying to the legislation, these methods
are checks of the administration, surprise checks at the farms and samples that are taken for analysis.
Nonetheless, the controlling agency, the Algemene Inspectie Dienst (AID), concludes in 2009 for the 4th
year in a row that there is evidence of slight to sometimes severe violation of the law with respect to the
use of chemicals (AID, 2009). This is partly due to legislation that has been tightened up in 2005. Some
growers possibly still possess the chemicals used in 2005 that are not allowed anymore since. In some
cases these were substantial amounts, and would imply an economic loss when thrown away. But this is
of course not an acceptable reason after 4 years of new legislation. It is assumed that most rose growers
that use forbidden chemicals buy and use them on purpose (Argos, 2010). The explanation mostly given
is that the chemicals still allowed to counter pests are not adequate. The rose grower providing the case
information (Dobbe, J. pers. com. 2010) for this report told the researcher that he felt that his hands were
tied. Public organizations (Argos, 2010; Natuur & Milieu, 2010) and politic parties (Partij van de Dieren,
2010) claim that the AID is unwillingly to prosecute the rose growers that break the law.
The harsh legislation has two downsides. The first is the obvious use of the currently forbidden chemicals
and the second is the high use of the currently still available chemicals (CBS, 2010; Dobbe, pers. com.
2010; Vermeulen, pers. com. 2010). Eventually one can only conclude that the present legislation in the
Netherlands is to strict for the type of rose cultivation practiced.
This leads to three options:
1. The legislation has to be softened.
2. The Netherlands has become an unsuitable place to produce roses.
30
3. Continuation of the current situation with harsh legislation but soft or inadequate punishments
when violating it.
The first option is seen as extremely unlikely to happen. The second and third options are seen as two
options that need not interfere with each other. Rose production in the Netherlands is decreasing every
year in the last decade (CBS, 2010; FloraHolland, 2010). The researcher suspects that the seeming
unwillingness of the AID to penalize the rose growers is to be attributed to their bad situation. It seems
cruel to be harsh to a part of industry that is experiencing very hard circumstances and which will
probably decrease to insignificant proportions in the coming decade anyway.
5.4.2 Pesticide use in Ethiopia
The amount of pesticides used in Ethiopia is extremely hard to estimate. There are no statistics kept by
the Ethiopian government where the researcher is aware off and no case information has been provided on
this subject. Former studies which have been conducted having as goal to compare greenhouse products
produced in the Netherlands to their competitors in warmer countries indicate a substantial higher use of
pesticides in the warmer countries compared to the Netherlands (Van der Brink, 2006; Verhaegh, 1996).
Verhaegh (1996) even states that the amount of pesticides used in the Israeli rose growing business is
twice the amount used in the Netherlands. This pattern is the same for tomatoes originating from either
Israel or Spain. Conversations with experts on this subject and people that have been on the rose growing
farms themselves also indicate a high use of pesticides. These experts also suspect the use of commonly
unaccepted chemicals by the rose farms.
Morris (2006) reports the bad conditions under which the Ethiopian companies store their chemicals and
criticizes the way the water used to clean spray equipment is treated. This report was made to evaluate
what was needed to better the Ethiopian floricultural sector to an internationally acceptable level. This
report was simultaneously a preparation of the Code of Conduct that would be composed in 2007. Due to
the birth of Code of Conduct one cannot conclude that the situation is still as reported by Morris in 2006.
The Code of Conduct has been made by the Ethiopian rose growers themselves is primarily concerned
with the health of the employees. This is presumably a reaction to the unrest that rose in the Ethiopia
itself. It is remarkable that although this code was launched in 2007, employees of rose farms claimed to
have become ill due to the chemicals used (Amera & Aklilu, 2008; Obole, 2008; Van der Schaaf 2008).
These articles are all written after the publication of the Code of Conduct. The unrest was clearly not
taken away by the introduction of the Code of Conduct. The code does not elaborate on defining impacts
of pesticides on the environment. Neither is there a list of conditions which specify how much and how to
use pesticides to diminish the impact on the environment. The code does mentions the abandoning of the
use of methyl bromide. This means that methyl bromide has been used in the past, and as the code leaves
room for exceptions, it is expected that some rose growing farms still use it to sterilize the soil. Methyl
bromide is toxic for animals and humans (Calvert et al., 1998; Honma, Miyagawa, & Sato, 1986; Wester,
Canton, & Dormans, 1987) and it has ozone depleting abilities. Therefore the Montreal convention states
that the use of this product has to be phased out. The use of methyl bromide in Europe has been declining
linearly since 1994 and is nonexistent since 2008. The assumption that more pesticides are used in the
Ethiopia than in the Netherlands is justified by the fact that in Ethiopia legislation on this subject is
minimal and the level of supervision poor. This is aided by the fact that the Ethiopian rose is cultivated in
open soil, which has to be sterilized once in every 4 to 5 years.
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Table 5-4: Pesticide use & application
Value
Dutch system
Ethiopian system
Amount of pesticides used
Codes to comply to
80-90 Kg
Dutch legislation, MPS
Unknown, > 90 kg.
Code of Conduct, MPS
Method of spraying
Mechanical
By hand.
Runoff of pipe cleaning to.
Sewer / Surface water
Sock pits / Ground water
Average disintegration time
Minimal,
Medium.
Maximal disintegration time
Supervising agency
Medium
AID, MPS
Long
EHPEA, MPS
Quality of the supervision
Medium
Poor
Percentage using IPC*
50-75%
0-50%
5.5 Results summarized
The Dutch system and the Ethiopian system score differently on the different aspects looked at. Which of
the results shown in this report are more important than others dependent on the location. One can
imagine that in arid areas the water factor is more important than most of the other results. To get an
impression of the results on the different fields the following figure has been developed. The
sustainability of the two systems on the different fields discussed are assessed.
Figure 5-2: Sustainability on different fields evaluated.
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The sustainability in Figure 5-2 is expressed relatively, expressing the relative sustainability of the system
on that subject. It is important to realize that this relative sustainability does not mean that for example a
specific rose growing company in Ethiopia by definition is unsustainable on the aspect water. The
numbers are meant to indicated the constraints and possible upcoming problems in the systems. From
Figure 5-2 it becomes clear that the systems differ strongly. Ethiopian greenhouses will encounter
sustainability problems with water, fertilizers and pesticides. Water is scarce in the country and the effects
on the environment on that subject are unpredictable. Due to the fact that all the greenhouses are located
in just two closed basins the water overuse will become more evident and the fertilizers and pesticides
that run off from the farms will accumulate in the lakes on these basins. The Dutch system on the other
hand is extremely energy consuming and this will become a larger problem in the future, with higher
prices for energy and more social pressure to lower energy consumption. On the last subject one must
remark that creating jobs in Ethiopia is expected to have a positive effect on the economy of one of the
poorest countries on the planet.
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34
6. Scenarios
Several scenarios have been developed to simulate future developments in this field. Static and dynamic
scenarios have been designed. Both have been split up in two different versions.
1. Maintaining current situation (Protection of the Dutch rose growers with economic and environmental
measures).
2. Continuation of current developments
1. No extra regulations implemented.
2. Controlled continuation of current developments.
6.1 Maintaining current situation (Protection of the Dutch rose growers with
economic and environmental measures).
In this scenario the current situation is considered and what would be needed to at least maintain it. In
contradiction to what the current developments are, in which the Dutch rose growers are disappearing, we
consider the situation in which the government tries to preserve them.
There are several measures that could be installed to protect the Dutch rose growers. One of these
optional measures is to subsidize roses produced in the Netherlands. Problem here is that the roses
produced in African nations will always be cheaper on the auctions, ensuring a continuing loss of market
share by the Dutch rose growers. This leads to the conclusion that this measure will have a limited effect
unless import tariffs are installed on roses produced in foreign nations. Complicating this measure is the
fact that most of the roses imported into the Netherlands are exported again to the rest of the world.
Import tariffs can only be implicated on roses that will remain in the Netherlands. The amount of roses
sold in the Netherlands is only a fraction of the production capability of the Dutch rose growers.
Implementing subsidies will give the Dutch rose growers the possibility to gasp for air, at least for short
period of time. To be able to maintain themselves they will have to keep on distinguishing themselves
from the roses produced in African nations. The quality and beauty of the Dutch roses are still appreciated
currently, ensuring a higher price for their roses at the auction. It is not very realistic to assume that it is
possible to hold this situation for ever. The roses originating from Africa are expected to gain better
quality in time but remain cheaper than their competitors grown in the Netherlands (Ammerlaan, pers.
com. 2010; Dobbe, pers. com. 2010). To fully compensate for the differences in prices the Dutch
government would have to spend 360 million Euros annually (FloraHolland, 2010), which is obviously an
amount which is unaffordable and not in any sense in proportions to the possible revenues.
The question arises whether the government could protect rose growers from competitors by demanding
specific environmental aspects. One of them could be the demanding of a report that shows that the
company delivering the roses does not harm the local environment. An example is the Dutch Millieu
Effect Rapportage (MER) which has to be submitted before construction of a company can take place.
Again complications arise, as the Dutch rose growers use more energy compared to their Ethiopian
competitors. In principle this is a negative effect on the environment too, making measures which aim at
the bad influences on the environment of the Ethiopian rose producers hypocritical and a point of view
which cannot be defended towards the rest of the world.
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6.2 Continuation of the current developments
In this scenarios the current developments are extrapolated to predict future social and economic effects
as well as the effect on the environment.
6.2.1 Continuation with current legislations.
In the last 5 years the amount of roses sold at the auction that originated from the Netherlands declined
almost linearly. Nearly every year 100 million roses were produced less than the year before. If this trend
is sustained, the Dutch rose industry will have been disappeared in 2021. The reason this will presumably
not happen is because some rose species that need extra care and more expertise to cultivate them. This
expertise is easier found in the Netherlands, leaving some niche markets open for Dutch rose growers. But
as said, these are niche markets, and the bulk of the rose-production will disappear from the Netherlands.
As a lot of Dutch rose growers that stop producing in the Netherlands move to Africa. But as the new
roses cultivated in Africa are cheaper, the global market will presumably grow slightly. Increased wealth
in nations like for example Russia will also help the market expand. A big part of this growing market
could be filled by Ethiopia, as the country is even cheaper in production than its biggest competitors
(Kenya, Tanzania etc.). This may change though if the country is able to reach higher income levels for
the population. The conditions for which the rose growers can lease the soil in Ethiopia and the tax
measures of the Ethiopian government also play a role in this.
The growing Ethiopian rose industry creates jobs for the local population and decreases the trade deficit
of Ethiopia. Both are positive effects for the economy of Ethiopia. Although the rose production cannot
solve either problems, it can make a big effort to help the country out of the extreme poverty it is in now.
If the Ethiopian acreage with rose production grows in the same rate as it did in the last years several
dangers arise. With the current growth rate the amount of roses exported will have doubled in 2015. The
first biggest danger is the overuse of the scarce water resources in Ethiopia. One should consider the fact
that exporting roses from Ethiopia is also in fact a strange form of water exportation, as plants are made
up for more than 70% of water. The biggest contributor to water loss is the evotranspiration, which is
obviously increased when an arid area is turned into a rose farm. Water extraction from the rivers and
lakes can endanger the mere existence of the lakes and rivers in lower parts of the catchment. This on its
turn would have severe implications on the local environment. It is of extreme importance that spreading
of acreage is applied. The use of ground water can have negative influences on the environment too.
Water from the rivers and lakes can leak into the underground, lowering their water levels. Extreme
overuse can even lead to dry-up of aquifers in the underground, a common known effect.
Fertilizer use and pesticide use are important to monitor. In the open cultivation systems used in Ethiopia
the rest products leak away into the ground water or nearby surface waters. Effects can be minimal and
local when overuse is not present and acreage density is low. When one of these two conditions is not
accounted for there is a risk that too high amounts of fertilizer or pesticides find their into nearby surface
waters. This can eventually compromise the livability of the surface waters for fishes and other maritime
organisms. An overuse of fertilizers can cause eutrophication of the surface waters leading to an extreme
growth of algae, which on their turn use up all the available oxygen. Pesticides can be toxic for a lot of
organisms when present in high concentrations.
When uncontrolled growth is tolerated and flower farms are allowed to settle wherever they wish (This
means near the capital) there is a high risk that water will be overused locally. This can eventually have
implications for the lakes and rivers in the lower parts of the basins. Eutrophication is, especially due to
the fact that these are all endorheic basins, very probable. This has been shown in the case of Koka lake.
Pesticide use is expected to have only local effects, but these can be very radical for the local flora and
fauna.
36
6.2.2 Controlled continuation of current developments.
As shown in the scenario explained in chapter 6.2.1, the current developments are good for the economy
of Ethiopia. This could come with a price for the local environment though. To avoid these negative
effects the Ethiopian government should take some additional measures. First of all the density of flower
farms should be kept to a minimum, to avoid the local overuse of water, fertilizers and pesticides.
Secondly, the overall amount of flower farms in an endorheic basin should not surpass a certain level. The
specific location of this level is not totally clear yet, more research on this subject is needed.
The Ethiopian government should support companies to settle in areas with more precipitation (The
Eastern part of country, where the river Nile has its origin). Together with a possible obligation to use
collected rainwater the local pressure on water resources can be lowered. If companies where to settle in
the eastern parts of Ethiopia a better connection with Addis Abeba would be needed. This connection can
be in the form of a better road or in the form of a better airport and air transport to Addis Abeba. This area
receives 1 to 2 meters of precipitation a year, which also means that there are less hours of sun per day.
Companies could be reluctant to settle here, as there are better locations from that point of view.
Unfortunately the amount of sun hours is nearly always negatively coupled to the amount of precipitation.
To lower the amount of pesticide used, IPC has been introduced in 2008 (Elings, 2008). IPC can lower
the amounts of pesticides used significantly. It is not clear how many rose farms in Ethiopia are
implementing IPC. As the industry is still developing it is not likely that IPC is already used in most
farms, as it would bring extra risks in the startup period of the farms. IPC also brings complications, as
some chemicals against fungi cannot be used anymore. A possibility to counter fungi is to ventilate more
and so create a lower humidity in the greenhouse. This has as negative consequence though that the water
use would increase.
The best option in this case would thus be to place the rose farms in areas of Ethiopia which receive more
precipitation. This has as downside though that these locations are more humid and thus increase the
danger of fungi. An extra negative side effect is the lower amount of sun hours per day.
In the endorheic basins in central Ethiopia there is a limited capacity for irrigated agriculture. If the
acreage of rose farms is to be increased, it is advisable to lower the acreage of the cultivated land for other
agricultural products. Another possibility is to make the irrigation in these agricultural areas more
efficient, as the irrigation systems that are used at this moment are very inefficient (Hengsdijk & Jansen,
2006).
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38
Conclusion
The Ethiopian rose cultivation systems and the Dutch cultivation system are significantly different. In the
current situation the Ethiopian system definitely has more future economically seen. The Ethiopian
economy will profit from this development. Dangers for the local environment are eminent though, and
need attention. If controlled, the Ethiopian rose sector can grow even larger in a sustainable way. To
facilitate this, the government of Ethiopia must place efficient and objective controlling agencies in place.
The Dutch rose cultivation is in serious danger of diminishing to minimal proportions. It is not likely that
this trend will stop. The part of the roses on the auctions that originate from the Netherlands will
presumably decline to insignificant proportions before the year 2025. The costs for energy and labor are
too high to keep on competing with African nations.
The rose that will be bought by the consumer will thus be a more climate neutral rose, and perhaps even a
development aid rose. However, that same rose will pose a danger to water resources in some areas in the
world and will have demanded more fertilizers and pesticides compared to the current Dutch rose.
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40
Discussion
Several difficulties were encountered in the process of this research. These problems are the following:
1. Absence of statistics on several subjects.
2. Unwillingness or inability to provide information by involved persons and companies.
3. The absence of personal observations and measurements to confirm statements.
The problems are numbered in order of importance. In general statistics on the rose production system in
Ethiopia are minimal or absent. It is recommendable to the Ethiopian government to improve the
transparency as the current situation is a feeding ground for speculations about the Ethiopian rose
production.
The energy use in the Dutch system is more or less 24 times higher than the energy use by the Ethiopian
system. Combined with the knowledge that this primary energy is composed of more than 99% of fossil
fuels (CBS, 2010; IEA, 2009; Wilting, 1996), one can say that the environmental impact in the form of
fossil fuel depletion and climate change is far bigger in the Dutch system.
Further research is needed on the impacts of the water use by the rose farms in Ethiopia. The researches
should assess the total water cycle in the specific endorheic basins. Water use by other agricultural
systems in those areas is of great importance to assess as well. These researches could then determine
whether more farms are sustainable and what the best locations for these rose cultivating farms would be
to minimize their impact. Local observations and good communication with the companies cultivating the
roses and the Ethiopian government will be a necessity.
41
42
Appendix: Common pests in rose cultivation
Three pests are considered the most damaging and most common in the cultivation of roses. These are
thrips, red spider mites and mildew.
Thrips are small insects that incorporate a huge family. The most commonly known of this family are
perhaps the thunder flies or storm flies that emerge after tropical rains. Although there is an enormous
amount of different described Thrips (over 5000 described) there are only a few that are harmful to
flowers. The thrips that are harmful to flowers have a length of approximately one millimeter and are
attracted to bright colors, which are obviously abundant in a greenhouse were roses are grown. These
Thrips are called the 'western flowers thrips'. They are attracted by to flowers and try to feed on them by
sucking the juice that runs through the plants vessels, thus extracting valuable sugars and other nutrients.
Thrips can be countered by the use of chemicals and by natural predators.
The red spider mite belongs to the well know family of mites, which can be found in every bed for
example. These mites often live in symbiosis with other animals. This is attributable to the honeydew that
the mites produce. As they suck up the plant juice, they take up far more sugars then they can use. The
surplus of the sugars they take up is emitted in small sugar rich droplets which are called honeydew. This
honeydew is very wanted among insects like bees, ants and wasps. They tend to protect the mite in
exchange for the honeydew. A second negative effect of these mites is the honeydew itself, as it
suffocates the plant leaves and it attracts, besides the insects, fungi too. The red spider mite and the thrips
have in common that they also serve as a vector for viruses, which they transmit when they are feeding on
the plant. As for the thrips, red spider mites can be countered by the use of chemicals and natural
predators.
Mildew is a fungus, it thrives in humid areas and can be found on your shower curtain for example. The
fungus creates spots and stains. The types of mildew typical to be found on roses are primarily Powdery
Mildew and in less abundance Downy Mildew. Both are countered by the use of Sulphur. Sulphur is
being gasified and spread through the greenhouse. The Sulphur then falls down on the leaves of the roses
and kills the mildew. The Sulfur also has negative effects for thrips and red spider mites. Mildew can also
be countered by synthetic chemicals.
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44
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