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Black Henbane

Hyoscyamus niger (hy-oh-SY-ah-mus NY-jer)

Family: Solanaceae Non-native Herbaceous

The genus name is derived from the words hog and bean, that refer to the severe toxicity that the plants seeds are to the swine population. Animals tend to avoid this plant due to its foul odor and taste. Black Henbane is an erect annual or biennial herb with coarse, hairy stems. Early in a plants' growth, it will appear in the form of a rosette before forming stems. When it grows as a biennial it will have many branches. An annual plant will have minimal branching. It is commonly found growing in rocky, temperate locations, often along roadsides as well as disturbed locations and beach areas. Although not native to the US, it has been introduced and can be found across the Northeast, the Midwest and a large portion of the West. It was brought to the US for cultivation as a medicinal herb. Although the leaves, fruits, seeds and roots are highly toxic, in ancient times, these plant parts were used to treat pain as a local anesthetic. During the Middle Ages, it was associated with witchcraft, where the common name Witches Herb came about. The flowers are tubular and 5-parted, with the petals fused into a cup shape. They are greenish-yellow or yellowish with purple veins and form at both ends of the stems, in spaces between the leaves and stem. The base of each flower is covered with long hairs. Annual black henbane bloom later in the season than the biennial. This invasive plant spreads by self-seeding. The seed dropped by the plant can remain viable for many years. Control can be accomplished by pulling or digging up the plants, ensuring to remove the taproot. Place plants removed in bags to contain the spread of seeds from mature fruits. When handling the plant, be sure to wear gloves, as exposure to the skin may cause a rash. Insects, Diseases, and Other Plant Problems: No significant problems.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 59 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.

Full plant profile

Growing Conditions
Plant type
Annual; Herbaceous Perennial; Poisonous; Weed
Life cycle
Annual; Biennial
USDA zones
4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b
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
Loam (Silt); Sand; Shallow Rocky
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage
Available space
12 inches-3 feet; 3 feet-6 feet
Growth rate
Medium
Maintenance
High
Canopy layer
4 - Herbaceous
Form & Appearance
Habit / form
Erect
Texture
Coarse
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Lanceolate; Oblong
Leaf margin
Lobed; Serrate
Leaf feel
Velvety
Leaf size
> 6 inches long, > 6 inches wide
Hairs present
Yes
Leaf detail
The hairy leaves feel sticky to the touch. The lower leaves have a short stem, the upper leaves have no stem.
Flower color
Gold/Yellow; Green; Purple/Lavender
Flower value
Showy
Flower form
Raceme
Flower shape
Bell; Cup; Tubular
Flower size
1-3 inches
Flower detail
Formed in the leaf axils, the flowers are axillary, tubular, 5-parted, greenish yellow or yellowish with purple veins.
Bloom time
Fall; Summer
Fruit type
Capsule
Fruit size
1-3 inches long, 1-3 inches wide
Fruit detail
The fruit is in the form of a pineapple or egg shaped capsule that will split open when ripe. Each capsule contains up to 200 seeds.
Stem color
Green
Stem detail
The stems a coarse and hairy.
Wildlife & Ecology
Native status
Non-native
Origin
Southern and Central Europe and Eurasia
Wildlife value
Harmful to wildlife, but rarely consumed.
Play value
Attractive Flowers; Easy to Grow
Food & Medicine
Fruit type
Capsule

Uses (ethnobotany)

Considered a weedy plant.

Landscape Use
Garden tags
#showy flowers #purple #biennial #poisonous #medicinal #poisonous root #poisonous leaves #wet soils intolerant #poisonous if ingested #self-seeding #poisonous fruits #skin irritation #annual #drought tolerant annual #drought tolerant #aggressive #weedy
Problems & Resistance
Problems
Poisonous to Humans; Problem for Cats; Problem for Children; Problem for Dogs; Problem for Horses; Weedy
Propagation
Seed
Poison severity
High
Poison parts
Bark; Flowers; Fruits; Leaves; Roots; Sap/Juice; Seeds; Stems
Poison symptoms
Poison Delivery Mode: Ingestion Symptoms: Salivation, headache, nausea, vomiting, diarrhea, rapid pulse, convulsions, coma
Toxic principle
Tropane alkaloids
Contact dermatitis
No
Toxicity summary
High severity poison; parts: Bark; Flowers; Fruits; Leaves; Roots; Sap/Juice; Seeds; Stems

Planted at Hunnicutt

Nobody’s planted this one yet.