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Bog onion

Arisaema triphyllum (air-ih-SEE-mah try-FIL-lum)

Family: Araceae Native Herbaceous (1-3 ft)

Commonly called Jack-in-the-pulpit, this native plant is a spring woodland wildflower, usually growing 1- 2' tall. The spadix or 'Jack' has a columnar form with a sheath that is called a spathe or 'pulpit'. Flowering plants initially produce only male flowers, but become hermaphroditic as they further age (male flowers on the upper part of spadix and female on the lower part). Most plants in a colony will vanish by mid-summer (become dormant), but the mature, hermaphroditic flowering plant will produce a cluster of red berries in mid to late summer which becomes visible as the spathe withers. Roots contain calcium oxalate (same chemical as in Diffenbachia or dumb cane) and are poisonous. This unique plant, which is pollinated by flies and gnats, has the ability to change sex. A plant that starts out as male can spontaneously change to female the next year and vice versa. Pollinators crawl beneath the spathe, down the spadix while collecting pollen. Spreading by cormlets sent out from the main root allow this plant to colonize. It also produces rhizomes. Jack-in-the-pulpit is best grown in fertile, medium to wet soil in part shade to full shade. It needs constantly moist soil rich in organic matter. It does poorly in heavy clay soils. It may be grown from seed, but takes five years for the plant to flower. This plant is generally found in a forest or natural area in moist woods, along creeks, or in the landscape, as a cultivated herbaceous perennial. The presence of concentrations of calcium oxalate crystals cause this plant to be toxic to humans when ingested. It also deters wildlife such as deer from consuming the foliage. Allow heavy, leafy cover should be allowed to remain through the winter months. Propagation can be accomplished by division or from seed. When the seed method is used, it can take up to 2 years for germination to occur. Insects, Diseases, and Other Plant Problems: No significant insect or disease issues. More information on Arisaema .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 71 attributes.

How it fits the guild

Guild layer 4 - Herbaceous (1-3 ft) 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 Arisaema ringens

Full plant profile

Growing Conditions
Plant type
Herbaceous Perennial; Native Plant; Poisonous; Wildflower
Life cycle
Perennial
USDA zones
4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
Light
Deep shade (Less than 2 hours to no direct sunlight) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
High Organic Matter
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist | Occasionally Wet
Available space
Less than 12 inches
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 1 ft. 0 in. - 2 ft. 6 in. | Width: 1 ft. 0 in. - 2 ft. 0 in.
Growth rate
Medium
Maintenance
Low
Canopy layer
4 - Herbaceous (1-3 ft)
Form & Appearance
Habit / form
Erect
Texture
Medium
Foliage
Deciduous
Leaf color
Green
Leaf type
Compound (Pinnately , Bipinnately, Palmately)
Leaf arrangement
Other/more complex
Leaf shape
Ovate
Leaf margin
Entire
Leaf feel
Glossy
Leaf value
Showy
Leaf size
> 6 inches long, 1-3 inches wide
Hairs present
No
Leaf detail
Jack-in-the-pulpit has one to two leaves, originating at the base of the stem that is divided into three almost equal leaflets. More specifically, two large green, compound, long-petioled leaves (1-1.5' long), divided into three leaflets each, emanate upward from a single stalk and provide umbrella-like shade to the flower. The fleshy stalk and leaves lend an almost tropical aura to the plant.
Flower color
Brown/Copper; Green; Purple/Lavender; White
Flower value
Showy
Flower form
Solitary; Spadix
Flower shape
Tubular
Flower size
3-6 inches
Flower detail
Jack-in-the-pulpit has club-like spadix with tiny flowers at the base, with green or purple hood, often marked with whitish stripes (though it could have purple or brown stripes on a green hood). Blooms from March to April. More specifically, the flower structure consists of the spadix (Jack) which is an erect spike containing numerous, tiny, green to purple flowers and the sheath-like spathe (pulpit) which encases the lower part of the spadix and then opens to form a hood extending over the top of the spadix. The outside of the spathe is usually green or purple, and the inside is usually striped purple and greenish white, though considerable color variations exist.
Bloom time
Spring
Fruit color
Red/Burgundy
Fruit type
Berry
Fruit value
Showy
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
Bright red, berry-like fruit. Displays from June to October. Each berry can contain 1 to 5 seeds.
Wildlife & Ecology
Native status
Native
Origin
Central & E. Canada to Central & E. U.S.A
Distribution
Throughout
Wildlife value
The fruits are eaten by songbirds and eastern box turtles.
Attracts
Pollinators; Reptiles; Songbirds
Play value
Easy to Grow; Wildlife Food Source
Food & Medicine
Harvest time
Fall; Summer
Fruit type
Berry
Landscape Use
Landscape location
Naturalized Area; Woodland
Landscape theme
Cottage Garden; Native Garden; Pollinator Garden
Design feature
Mass Planting
Garden tags
#purple #poisonous #moist soil #deciduous #spadix #turtles #rich soils #fire low flammability #edible garden #native garden #NC native #native wildflower #food source summer #food source pollen #Piedmont Mountains FACW #Coastal FACW #food source fall #spring interest #bird friendly #stream banks #HS302 #problem for dogs #problem for horses #problem for cats #spring flowers #tropical feel #Audubon #food source soft mast fruit #partial shade tolerant #heavy shade tolerant #wet soils tolerant #shade garden #white flowers #showy fruits #red fruits #showy flowers #showy leaves #clay soils intolerant #showy #colonizing #striped leaves #long lived #wildlife friendly #woodland #wildflower #herbaceous perennial #HS304 #contact dermatitis
Problems & Resistance
Problems
Poisonous to Humans; Problem for Cats; Problem for Children; Problem for Dogs; Problem for Horses
Resistant to
Deer; Fire; Heavy Shade; Wet Soil
Particularly resistant to
heavy shade, deer, wet soil, fire in the landscape
Propagation
Division; Seed
Fire risk
low flammability
Poison severity
Low
Poison parts
Bark; Flowers; Fruits; Leaves; Roots; Seeds; Stems
Poison symptoms
CAUSES SEVERE PAIN IN THE MOUTH IF EATEN! Poisonous through ingestion. (Poisonous parts: all parts). Symptoms may include: Irritation and swelling of lips, tongue, and throat, excessive drooling, and vomiting (not horses). [For example, the roots contain calcium oxalate (same chemical as in Diffenbachia or dumb cane) and are poisonous.]
Toxic principle
Calcium oxalate crystals
Contact dermatitis
No
Toxicity summary
Low severity poison; parts: Bark; Flowers; Fruits; Leaves; Roots; Seeds; Stems

Planted at Hunnicutt

Nobody’s planted this one yet.