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Devil's Tongue

Amorphophallus konjac (a-mor-fo-FAL-us KON-jak)

Family: Araceae Non-native Herbaceous

Voodoo lily is a cormous, herbaceous perennial plant native to forest margins and thickets in China but naturalized throughout much of eastern Asia. It is a member of the arum family (Araceae). The plant is widely cultivated in Japan and China as a food source and as an ornamental. The species epithet is a transliteration of the Japanese common name for this aroid. Voodoo lily grows best in moist but well-drained, humus-rich, fertile soil and dappled shade. It does not tolerate clay soil. Avoid hot, afternoon sun, especially when the leaf first emerges and is most sensitive to scorching. Plants tolerate a minimum temperature of 60 degrees F during the growing season, though the optimum range is 68 to 77 degrees F. Fertilize regularly. Reduce watering during the winter dormant period. The leaf and inflorescence are intolerant of frost, but the corm is hardy. Propagate from offsets (cormels) or seeds. The plant produces one enormous leaf from the corm and one flowering stem annually. The large showy flowers are purple and appear in the spring. When fully open, the spadix heats up and emits an odor of rotten flesh that attracts carrion flies and midges, which pollinate the flowers. The smell disappears once the flowers have been pollinated. It has glossy brown edible corms (bobo-tuber) that produce cormels each year. The corm is edible but contains calcium oxalate that makes it toxic if consumed raw. The voodoo lily is more curious than beautiful and can be grown in an Asian-themed garden or a sensory garden. It makes an interesting greenhouse subject or houseplant, but it must be moved outdoors when in flower, as the stench in an enclosed space is overpowering. Diseases, Pests, and Other Plant Problems: No known diseases or insect pest issues. More information on Amorphophallus .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 51 attributes.

How it fits the guild

Guild layer 4 - Herbaceous Optimal soil pH Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Often confused with Amorphophallus kiusianus

Full plant profile

Growing Conditions
Plant type
Bulb; Edible; Herbaceous Perennial; Houseplant
Life cycle
Perennial
USDA zones
6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b, 11a, 11b
Light
Dappled Sunlight (Shade through upper canopy all day) | Deep shade (Less than 2 hours to no direct sunlight) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Loam (Silt); Sand
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist
Growth rate
Rapid
Maintenance
Medium
Canopy layer
4 - Herbaceous
Form & Appearance
Habit / form
Erect
Leaf color
Green
Leaf type
Compound (Pinnately , Bipinnately, Palmately)
Leaf value
Showy
Leaf size
> 6 inches long, > 6 inches wide
Hairs present
No
Leaf detail
A bipinnate, highly divided, single leaf with a pink leaf stem grows from a corm. The leaf grows up to 39 inches long while the corm grows up to 1 foot in diameter. The stem can reach 4 to 5 feet tall.
Flower color
Brown/Copper; Purple/Lavender; Red/Burgundy
Flower value
Fragrant; Showy
Flower form
Spadix
Flower size
> 6 inches
Flower detail
When the corms reach maturity they produce an inflorescence before the leaf emerges. The aroid-type infloresence is made up of a dense, spike-like spadix which bears numerous, small, male and female flowers and a leafy, dark maroon to purple-brown spathe with ruffled margins. The 3 to 4 foot tall bloom emits a strong odor of rotten flesh to attract pollinators.
Wildlife & Ecology
Native status
Non-native
Origin
East Asia and southwest China
Distribution
Primarily Asia
Attracts
Pollinators
Food & Medicine
Edible parts
Tubers

Edibility

The tubers are starchy and edible when cooked like a potato. It is commonly dried and ground into a flour and used in noodles and tofu. Can be toxic if eaten raw.

Uses (ethnobotany)

Used as a food source and traditional medicine in Asia. In Japan, the corm is known as a great source of Konnyaku, a type of flour used in many dietary products, and jelly.

Landscape Use
Landscape location
Container
Landscape theme
Asian Garden; Garden for the Blind
Design feature
Accent
Garden tags
#malodorous #spadix #poisonous #colorful leaves #th-smell #corm #houseplant #edible #container plant #tropical evergreen
Problems & Resistance
Disease problems
Damping-off in Flower and Vegetable Seedlings
Problems
Malodorous
Propagation
Seed
Poison severity
Low
Poison parts
Leaves; Roots
Poison symptoms
Toxic if eaten raw. This plant belongs to a family where members contain calcium oxalate crystals which, if eaten, makes the mouth, tongue and throat feel as if small needles are digging in to them. Calcium oxalate is broken down by thoroughly cooking the plant or by fully drying it, rendering it safe to eat. People with a tendency to rheumatism, arthritis, gout, kidney stones and hyperacidity should take especial caution if including this plant in their diet.
Toxic principle
Needle-like, calcium oxalate crystals; possible proteins.
Contact dermatitis
No
Toxicity summary
Low severity poison; parts: Leaves; Roots

Planted at Hunnicutt

Nobody’s planted this one yet.