Community Gardens on
Brownfields:
Opportunities, Challenges, and
Strategies
Kristen McIvor, PhD
Tacoma/Pierce County Community Gardening Program
[email protected]
What are Community Gardens?
Any piece of land gardened by a group of people.
From the American Community Gardening Association
Or
Also – “Community-managed Open Space.”
What do we find in community gardens?
They are as diverse as the
neighborhoods in which they are
created.
We find: organic vegetables, flowers,
fruit, gathering spaces, children’s areas,
places for education, composting,
wildlife habitat areas, orchards, rain
gardens, and much more.
What’s the big deal?
In my humble opinion, community gardens are much more that places
where people turn vacant lots into nice gardens – their effects are profound
and far-reaching.
They are fundamentally about reconnection.
To our environment
To our food supply
To each other
There are some problems we’re facing today
Degraded urban environment – lack of understanding of natural cycles (and
lots and lots of waste)
Unhealthy relationship with food
Loss of ability and opportunity to engage in citizenship – too often we are
solely consumers…
People are seeing this as an exciting opportunity
Yellow – existed in 2008
(11 – 9 gardens and 2
orchards)
Pink – new since 2008 (29)
Purple – coming soon! (9)
Gardens are on a diversity
of public (City, Parks,
School) and private (church,
private citizen, housing
complex, land trust) land –
each one is incredibly
unique!
Where do we start?
To support communities in doing this – there are two parts:
Community – a Community garden without gardeners is just a
vacant lot. Do not underestimate the importance of this!
Garden – Many different types of land can be utilized – almost
anything can work if the social piece is there (and some sun!)
Strategies – Know what you’re working with
Land Use
Common Contaminants
Agriculture, green space
Nitrate, pesticides/herbicides
Car wash, road and maintenance depot,
vehicle services
Metals, petroleum products, sodium, solvents,
surfactants
Dry cleaning
Solvents
Junkyards
Metals, petroleum products, solvents, sulfate
Machine shops and metal works
Metals, petroleum products, solvents,
surfactants
Stormwater drains and retention basins
Metals, pathogens, pesticides/herbicides,
petroleum products, sodium, solvents
Underground and aboveground storage
tanks
Pesticides/herbicides, petroleum products,
solvents
Wood preserving
Metals, petroleum products, phenols, solvents,
sulfate
Chemical manufacturing, clandestine
dumping, hazardous material storage and
transfer, industrial lagoons and pits,
railroad tracks and yards, research labs
Fluoride, metals, nitrate, pathogens, petroleum
products, phenols, radioactivity, sodium,
solvents, sulfate
(Adapted from Boulding and Ginn, 2004)
Chart from EPA’s publication Brownfields and Urban
Agriculture: Interim Guidelines
for Safe Gardening Practices
8
Strategies – Test your soil
Not all urban soil is contaminated – not even all brownfield properties – Use soil
testing to understand the situation on your chosen property.
•Basic vs. Rigorous – based on prior use, narrow the list to likely contaminants
(testing for all potential contaminants is impractical and expensive)
•Take samples throughout the site (composite sample)
•Send a sample for testing (many state universities have good testing labs)
•Kansas State http://www.agronomy.ksu.edu/soiltesting/
•Penn State http://www.aasl.psu.edu/SSFT.HTM
•Soil control Lab http://compostlab.com/index.htm
•Also good to test for nutrients while you are at it
9
Strategies – Understand the risk
Different contaminants pose different risks depending on how the contaminant
reaches humans
Two primary risk pathways
•Soil – Plant – Human
•Soil – Human
10
A bit more on Lead - the most common contaminant
Many urban sites have high lead levels due to its ubiquitous use in paint and
gasoline
Lead does not get taken up into plants (carrots take up the most, still only
minimal); the primary risk is the soil-human pathway
Lead is not mobile in the soil – it stays where it lands
-highest concentrations will be near streets and houses
-tilling the soil will incorporate it and reduce overall concentrations
EPA says that Lead over 400 ppm is a concern – this doesn’t mean that you
shouldn’t garden there – you should pay attention, but contamination is
generally localized, and you can minimize risk enough to make it safe.
Increasing fertility in soils (especially P) will reduce risks from lead.
11
Strategies – Make a plan
Now it’s time to make a plan – take into consideration:
•Type of contaminant
•Concentration of contaminant
•Relevant risk pathway
Decide whether to amend
existing soils or build raised beds
Talk to your local EPA office if
you are unsure or need help
interpreting you soil results!
12
Amending in-ground soil
•For some sites – amending the existing soils with organic matter will serve to
reduce risk
•Compost, Class A biosolids and other forms of organic matter can reduce
concentrations of contaminant to below acceptable levels
•Also serves to improve soil quality for crop production and buffers pH
Pros: Affordable
Urban centers often have low-cost recycled organic waste products
available locally
Cons: May not be sufficient for all sites
Photo: Growing power 13
Building Raised beds
•For sites where in-ground amendment is not an option, garden beds can be
constructed out of many different materials and be used to hold soil above
ground.
•Soil or a soil-replacement product must be sourced to fill the garden beds
Pros: Sufficient to mitigate most contaminated site
Accessbility
‘Tidy’ factor
Often easier to work
Cons: Materials/Soils are costly
Requires skilled labor to construct.
**Pathways should also be considered – mulching with wood chips is a simple
solution – remember risk from inhalation is greater
Photo: Gardenerd
14
For very contaminated sites (or very concerned people)
Eating is a very personal act – many urban people do not understand soil
and are afraid of contamination.
•Landscape fabric in between beds can reduce soil/garden bed interface –
even if it is not necessary, can make people feel better
•Choose carefully which crops to plant (i.e. can choose to avoid root crops,
esp. carrots)
Other good (best!) practices
•Work to minimize exposure by removing exposure routes
•Put the garden in the cleanest place possible – many site are not
universally contaminated
•Educate people about the site and make sure kids don’t eat the soil
•Practice good hygiene (always a good idea!) – wear gloves, wash hands,
wash food
•Try not to track dirt into the house (take shoes off outside, etc.)
•Maintain soil at a neutral pH
Phytotechnology
•Some exciting research has been done in this area – look at EPA website
for more information
•On the garden scale – unless you have a scientist/researcher as part of
the group – not practical
•Does not work for lead.
What are we doing in Tacoma?
Working to support gardens by helping them acquire resources
•Tagro (Class A biosolids product)
•Compost (yard-waste compost product)
•Wood chips for mulching pathways
•Cardboard for smothering weeds
These are organic waste products from urban areas – by finding a new life for
them in community gardens, we are turning wastes to resources, improving
urban soil, and educating urban residents on the ecology of a city (there is no
away!)
What are we doing in Tacoma?
Partnering with local agencies to provide garden education classes (including soils)
for free!
What are we doing in Tacoma?
Working to cultivate a strong sense of ownership by the managers of the
Community Gardens – the gardeners themselves
Our model for Community Garden Development:
‘Communally-managed open space’
Challenge of Democracy in an accelerated world
Although we are more ‘connected’ through the internet then we have ever been –
we remain disconnected in fundamental ways.
Scholars note the challenge of maintaining a democratic culture when
people are too busy to participate in civic life
Contested democracy vs. collaborative space
Difference between engaging in democracy via hearings/protest and collectively
creating something new
VS.
Importance of Physical Space for Democracy
Michael Kimmelman in the NYTimes…
From Aristotle to #OccupyWallStreet
Bankruptcy of ‘public space’ in America – Created by developers, public spaces
"are not really public at all but quasi-public, controlled by their landlords.”
What are we doing in Tacoma?
‘Governing the Commons’, cont.
3.
Most individuals affected by these rules can participate in modifying the rules.
4.
The rights of community members to devise their own rules is respected by
external authorities.
5.
A system for monitoring member's behavior exists; the community members
themselves undertake this monitoring.
6.
A graduated system of sanctions is used.
7. Community members have access to low-cost conflict resolution mechanisms
What are we doing in Tacoma?
We use: Design principles for sustainable management of the commons
– from Elinor Ostrom “Governing the Commons”
1. Group boundaries are clearly defined.
•What the garden group has control over and what the landowner has control over
is clear.
•The needs of the landowner are communicated clearly to the group of gardeners
(esp. regarding appearance of the garden)
2. Rules governing the use of collective goods are well matched to local needs and
conditions.
•To the greatest extent possible, the group of gardeners should write the rules of
the garden.
The process
Gardener Starter questions – make your own rules!
•Vision/purpose
•Leadership
•Communication
•Maintenance
•Participation
•Other?
Process for Landowners:
•Vision/purpose
•Maintenance/Appearance
•Safety/liability
•Communication
•ADA accessibility
•Access/Parking
Gardens are an opportunity to participate in civic life – experiences
in democracy
•Not all gardens are created alike: Individual vs. communal
•The greater amount of communal space in a garden the higher the levels of social
capital
Questions?
Kristen McIvor, PhD
[email protected]
253.363.1846