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GROWING ARUM
(AKA Jack in the Pulpit, Wake Robin & Cuckoo Pint)
In
Texas
AN EXPERIMENT
Arum
Curtis Botanical
Magazine - 1796
While not widely known or grown, I am of the opinion that most Arum will do
well in North Texas. I am attempting to grow as many species as I can get in Fort
Worth. David Leedy – [email protected]
November 2013
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Arum Linnaeus (See Addenda for technical terms)
INTRODUCTION
Carl Linnaeus used the generic name Arum in his Species Plantarum (1753). The first record of
its use as a generic name was that of Fuchs (1542). However, the name Arum and its history
goes back much further. The first record of the name Arum is in classical Greek literature, both
Pliny and Discoridis giving details of more than one species of Arum known to them. According
to Cecil Prime in his book “Lords and Ladies”:
On the walls of a small temple of Thutmose III at Karnak, there is a series of limestone
bas-reliefs covered with plant drawings, dating from the fifteenth Century, B.C. Some
of the plants can easily be recognized as two kinds of Arum.
Arum are perennial tuberous herbs whose leaf emerges in early autumn to late winter. The most
widely known and grown species in North Texas is A. italicum, ssp italicum. The many cultivars
of that species as well as the sub species are not well known (or known at all) in North Texas.
PRIOR YEARS’ EXPERIENCE WITH ARUM
During the first year, growing of Arum was attempted in containers and, after the growing
period, the containers were emptied and all but one of the tubers stored inside of the home in air
conditioning. It was noticed that the single tuber (Arum orientale) left outside, in the shade
between a large tree and next to the wall of the house, suffered little from the summer heat. The
second year, many additional tubers were acquired and growing was again attempted in
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containers. However, there was almost 75% mortality of tubers in smaller (one gallon and less)
containers after a long, hard December rain followed by a week when the temperature did not
exceed freezing (32 degrees F., 0 degrees C.). However those tubers in 2-3 gallon containers
survived the inhospitable weather. The surviving tubers remained in the containers in the shade
between the large tree and the house for the hot summer. This experiment is the third growing
season at this locality and about 80% of the tubers are newly acquired.
PREPARING THE ARUM GARDEN
As the garden top-soil was so shallow, many colleagues suggested that a cold frame be
considered for growing Arums in Fort Worth. On the East side of the home, under a roof
overhang of approximately two feet, existed a garden of 32 feet in length and two feet in width.
This garden was built over a French drain (buried in the clay and shale at roughly 2 feet deep)
and outlined with a 4 inch thick, concrete wall to four inches above the soil line. All of the
existing plant material was removed and a planting mix of 50% sand and 50% compost was
added. Then to this was added 12 cubic feet of course perlite (in order to increase the drainage
of the soil). The garden now has a depth of approximately 28 inches. Without testing the Ph of
the soil, some agricultural lime was added to offset the acidity from the decomposed compost.
Depending on the size of the tuber (more shallow for smaller tubers) a 5” hole was dug, the
bottom 1± inches was filled with grit, and the tuber placed on top of it. Then the hole was
refilled. Although the garden soil should drain fairly well with the sand and perlite, the grit was
an added precaution against the accumulation of water around the tuber, which might cause
rotting. Each species/cultivar was separated by a thin wall (rubber edging cut into 20” lengths).
SPECIES/CULTIVARS INCLUDED IN THIS EXPERIMENT
Arum albispathum
Formerly a subspecies of Arum italicum, A. albispathum
has been designated a separate species, according to
Peter Boyce (author of “The Genus ARUM.”
Same habitat and flowering period as A. italicum, A.
albispathum is distributed in the Crimea and Caucasus.
Arum apulum
Sprouts in late summer from a vertical tuber
(discorid). Leaf is deep green. Spathe exterior
mid green and interior purple. Spadix dull
chocolate brown to pruple. Flowering period is
April.
Distribution is Southern Italy, (Puglia, known
only from Giolia to Colle).
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Arum byzantinum
Sprouts in late autumn from a rhizomateus tuber.
Flowers late May to early June with slender, whitishcream spathes, with a purplish basal stain and a red
purple line around the edge, wrap around strongly
club-shaped yellow spadix.
Distribution restricted to a small area of the Balkan
Peninsula between Bulgaria and Istanbul where it
apparently grows in the same damp soils which suit it
well in cultivation
Arum concinnatum (Possibly 3 forms. Received in 2013
from 3 different sources, each with differing descriptions.)
A concinnatum has a very potent, urine-like smell when in flower. The leaf is dark green
with splotches of silver gray. Spadiix is pale to mid-green at the base and usually flushed
with purple. Flowering period is March to early June and distribution is Greece (the extreme
southern tip of Peloponnese), most islands of E. Mediterranean, and coastal S.W. Turkey.
Arum creticum
Early, tuberous perennial from Greece . SW Turke;y
and Crete. Habitat is rocky, grassy hillsides, open
meadows amongst low scrubs.
Has large, glossy dark green, unmarked, arrow/spear
head shaped leaves. Bears creamy white or yellow
spathes which folds back to show the yellow spadix
March to May. Flwoers give off a nice scent not too
different from a rose smell.
Flowers March-May
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Arum cyrenaicum
Sprouts in early autumn from a discoid, vertical tuber.
Leaf blade is glossy, deep green. Green spathes with a
large purple-rose interior around a darker red-pink spadix,
scentless (Boyce says “smelling slightly of horse dung”).
Green spathes with a large purple-rose interior around a
darker red-pink spadix s in March to April. Habitat is open
scrub amongst boulders. Distribution is Libya (Cyrenaica)
and Greece (S. Crete). Does well in North Texas (Fort
Worth). Autthor’s plant seeded in 2012.
Arum cylindraceum
Formerly known as Arum alpinum.
Sprouts in early winter from a vertical tuber (discorid). Leaf is
dark green to mid green with the lower ¼ occasionally stained
in purple. Spathe is light green and Spadix is pale brown to
purple. Distribution: Throughout Europe
Arum dioscoridis
A very popular species among collectors, this plant has a large variation in the coloring of its
spathe from a light green with no spots, spotted forms, and to a deep purple.
Prefers a humus rich soil and abundant water in the growing season. Grows well in woodland
conditions. Succeeds in sun or shade. This species tolerates temperatures down to between -5
and -10° c. Because it comes into growth in the late autumn it is best grown by a warm wall.
Pollinated by flies and scent smells like dung or carrion in order to attract them.
Distribution (varies by variety): Aegean islands, Rhodes, Cyprus, Syria, Lebanon, Turkey,
and Israel.
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Arum elongatum
Sprouts in autumn from a discoid, vertically oriented,
tuber. Dark green leaves. Exterior of spathe is green
and interior is stained with purple.
Flowering period April - June.
Habitat is deciduous woodland.
Distribution is
Bulgaria, Greece. N. Turkey and Belorusssia.
Arum hygrophilum
Arum hygrophilum is native to Israel, Cyprus, and the Syrian-Lebanon border, where it
emerges from summer dormancy in fall with narrow, upright, 2' tall, light green, wintergrowing leaves. Arum hygrophilum is adorned, starting in March, with a lovely pale green
spathes, edged in purple and highlighted by a poorly-endowed, dark purple spadix. In mild
winters, Arum hygrophilum often tries to flower in late January, but cold knocks back the early
flowers. In the wild, Arum hygrophilum can be found by moist streambanks and in wet seeps
where it grows taller. Evenly moist garden soil has been perfect (according to Boyce).
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Arum italicum
Arum Italicum, ssp Italicum Arum ‘Chameleon’ Arum ‘White Winter’
Black spotted form
Warburg Strain
Gold Rush
McClements Form
This popular Arum, sometimes commonly called Italian Arum, is a woodland species,
native to Europe. Typically grows 12-18" tall. Flowers are produced in April - May.
After the bloom, the leaves and spathe die back leaving only the thick flower stem
(peduncle) which develops attractive, bright orange-red berries in summer.
Arrowhead-shaped, glossy grayish-green leaves with pale whitish-grayish-silverish
midribs, 8-12" long, emerge in November - December and remain evergreen in North
Texas (Fort Worth) winter climates. Best grown in medium moisture, consistently moist,
organically rich soils in part shade to full shade.
In addition to the above named varieties, the Fort Worth collection includes several
collected and unnamed/unidentified varieties.
A number of cultivars, some of which are shown above, are grown by Arum collectors.
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Arum korolkowii
Slender tapering and elongated green spathes wrap
around a disproportionately fattened pink-brown
spadix, making a remarkably attractive combination
and the plant is refreshingly unscented! Discoid,
vertically oriented tuber.
Flowering period April – May. Habitat is soil pockets
in rocky hillsides and beneath scrub. 1100 – 2500 m.
Endemic to North Iran, Afghanistan and central Asia.
Arum maculatum
All green form.
Spots on leaf.
The most widely known species in the UK, Arum maculatum has been given many names
(“Lords and Ladies,” “Cuckoo Pint,” “Jack-in-the-Pulpit,” etc).
Sprouting in late winter to early spring from a rhizomatious (horizontal) tuber. Glossy, deep
green foiliage often with spotting (black or maroon) and quite variable. See two varieties, above.
The flowering period is mid-April to late May. Habitat is open deciduous woodland.
Distribution throughout Europe from NW Spain to the Caucasus and from Sweden to Northern
Greece.
Arum nigrum
This species is native to the South Balkans.
The inflorescence is dark purple, about 7½” tall with
peduncle, blooming in early May. The spadix smells
unpleasantly. Reported as hardy down to 10° F.
Grows well in shady position with dampish, heavy soil
rich in organic matter.
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Arum orientale
Arum oreintale, var. longispathum
Sprouting in mid to late autumn from a discoid (horizontal oriented) tuber the leaf is
generally deep green. The flowering period is in late May. The spathe varies from light
green, to green with purple staining to completely dark purple.
Distribution extends from northern and western Turkey into eastern Europe and as far west
as Vienna. Found in open woodland in damp and shady places. The wide distribution is
accompanied by a wide variation in color and form. Some of these varieties have been
assigned varitel and subspecies names. (several of these in Fort Worth collection.)
Arum palaestinum
Sprouting in autumn from a discoid (usually vertically
oriented) tuber with deep green leaf. Spathe is green
to pale brown on the exterior and deep purple on the
interior. The flowering period in March to May.
Habitat is open hillsides, fallow fields and field
margins. Distribution in Syria, Lebanon, and Israel.
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Arum purpureospathum
Sprouting in early to mid autumn from a discoid (vertically
oriented) tuber. Large, polished, deep-green leaves around an
enormous spathe of deep rich purple-black wrapped around a
spadix of an even darker sháde. Very attractive Arum with little
scent, which is rare in the darker species.
A vigorous and very growable species for a sunny, well-drained
lime soil in full sun. Hardy in North Texas (Fort Worth)
Flowering period is March – April. Hillsides and short grass from
sea level to 100m. Distribution is Greece (SW Crete).
Arum rupicola
Sprouting in late winter from a discoid (vertically oriented
tuber), leaf stalks (petioles) about one foot high. Leaves are up to
4” long by almost 3” wide. The flowering period is April to
June. The inflorescence is held above the leaf level, (‘flag
species’) with a spathe almost 4”long by 2” wide and colored
green-cream to greenish-purple won the outside and either green,
cream or purple on the inside with a very large pale spadix. .
Variety virescens always has entirely greenish spathes and
variety cordatum has a larger spath but the color can be varied, as
described.
Distribution is in Turkey and Iran. It is found growing in
woodland and more open rocky places, often by water.
Arum (Gymnomesium) pictum
A winter-growing herb with a whitish tuber 2½” across. Arum pictum is unique in
the genus Arum with its autumn-flowering, and in this respect, as well as in its
horse dung-like scent, resembles members of the related genus Biarum. The arrowhead shaped leaves are about 12” long and 6” wide. At first they are shiny and
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purplish, later becoming silvery or whitish. The flowering stem (spadix) appears
with or before the leaves, and smells strongly of horse dung. Native to Majorca
(Mallorca), Minorca, Corsica, Sardinia and the west coast of central Italy.
Dracunculus Vulgariis (Black Arum)
Dracunculus vulgaris is a species of aroid in the genus Dracunculus and is known
variously as the Dragon Arum, the Black Arum, the Voodoo Lily, the Snake Lily,
the Stink Lily, the Black Dragon, the Black Lily, Dragonwort, and Ragons. In
Greece, part of its native range, the plant is called Drakondia, the long spadix being
viewed as a small dragon hiding in the spathe.
This plant can tolerate some shade but prefers full sun; it can also withstand
drought but benefits from a little watering. The plant prefers a humus-rich, welldrained soil.
It is endemic to the Balkans, extending as far as Greece, Crete, and the Aegean
Islands, and also to the south-western parts of Anatolia.
MEMBER for over 35 years.
MORPHOLOGY and BOTANY
MEMBER - FORT
WORTH BOTANICAL
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ADDENDA
Further Morphological and Botanical Infromation:
The tubers are either discorid (vertical) or rhizomatous (horizontal). The floral structure (spath
and spadix) generally emerges in late winter (January – February in Fort Worth) and the female
ovules convert to seed containing berries, when fertilized. The leaf withers in late Spring and the
berries turn to a bright reddish orange and remain on an erect stem (peduncle) until late June –
July. An exception to this is the plant previously known as Arum pictum, which flowers in the
autumn. Dr. Peter Boyce (Author of “The Genus Arum”) believes that Arum pictum may belong
to a separate classification: Gymnomesium , which may be a separate section of the genus Arum
or completely separate genus from Arum.
A.Spathe, B.Spadix, C.female ovules convert to seed containing berries
According to Boyce (The Genus Arum, page 35): There are two main types of
inflorescence found in Arum. Those species with spathes held near ground level, below
or just level with the leaves (‘cryptic species’) and produce a scent . Those species
bearing the inflorexcence above leaf level, (‘flag species’) are scentless, apart from A.
creticum. Ecologically the difference seems to be that the cryptic species invariably grow
in wooded or scrubby areas. The flag species usually inhabit open or rocky areas with
little or no overhead obstruction.
A. Cryptic.
B. Flag.
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LOCALITY AND FEATURES OF THIS EXPERIMENT:
Fort Worth
As shown on the above map, Fort Worth is located in North Central Texas, about 50 – 80 miles
west of Dallas. Fort Worth is the sixteenth most populous city in the United States of America
and the fifth most populous city in the state of Texas. Fort Worth has a transitional semi arid
climate.
The location of this experiment is in West Fort Worth, where the USDA hardiness zone is 7b
(average minimum temperatures of 5 – 10 degrees Fahrenheit). The coldest month of the year is
January, when the average high temperature is 55 °F (13 °C), and low temperatures average 31
°F (−1 °C).[ The coldest temperature ever recorded in is −7 °F (−22 °C), on December 24, 1989.
The hottest month of the year is July, when the average high temperature is 95 °F (36 °C), and
overnight low temperatures average 72 °F (23 °C), giving an average temperature of 84 °F (29
°C). The highest temperature ever recorded in Fort Worth is 113 °F (45 °C), on June 26, 1980
and June 27, 1980. Fort Worth is in the American Horticultural Zone 8, where the summer
average high temperatures are in excess of 86 degrees Fahrenheit for 91 to 120 days per year.
The average annual precipitation for Fort Worth is 34.01 inches (863.8 mm). The wettest month
of the year is May, with an average of 4.58 inches (116.3 mm) of precipitation. The driest month
of the year is January, with 1.70 inches (43.2 mm) of precipitation falls. The average annual
snowfall in is 2.6 inches (66.0 mm). Because of its position in North Texas, Fort Worth is very
susceptible to super-cell thunderstorms, which produce large hail and can produce tornadoes.