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Bog Hemp

Boehmeria cylindrica (beh-MEE-ree-ah sil-LIN-dri-kah)

Family: Urticaceae Native Herbaceous

False Nettle is a flowering, herbaceous perennial plant that is native to Canada and North America. It is commonly found on moist or shady ground, deciduous woods, swamps, bogs, marshes, wet meadows and ditches. The genus name honors the German botanist Georg Boehmer. The species name is based on the cylindrical spikes located in the leaf axils. False Nettle prefers the light shade and moist, well drained, rich loamy soil. In sunny locations, this plant prefers wetter ground and the foliage may become yellowish green. False Nettle is dioecious (meaning individual flowers are either male or female, but only one sex is to be found on any one plant), thus both male and female plants must be grown if seed is desired. The plant displays tiny greenish flowers in small clusters, arranged in continuous or interrupted spikes in the axils of opposite leaves. Although a member of the nettle family and, in appearance, like stinging nettles plants in this genus do not have stinging hairs on its opposite leaves. Use in the border of pollinator, native and woodland gardens. Diseases, Insect Pests, and Other Plant Problems: No known diseases or insect pests.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 54 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.

Fills a similar niche Ulmus alata Ulmus americana Viola striata

Full plant profile

Growing Conditions
Plant type
Herbaceous Perennial; Native Plant; Weed
Life cycle
Perennial
USDA zones
4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b
Light
Full sun (6 or more hours of direct sunlight a day) | 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
NC region
Coastal; Mountains; Piedmont
Growth rate
Medium
Maintenance
Low
Canopy layer
4 - Herbaceous
Form & Appearance
Habit / form
Erect; Multi-stemmed
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Opposite
Leaf shape
Lanceolate; Ovate
Leaf margin
Dentate; Serrate
Leaf feel
Rough
Leaf size
3-6 inches long, 1-3 inches wide
Hairs present
No
Leaf detail
Opposite (occasionally alternate) leaves with coarsely serrate margins 4 inches long and 2 1/2 inches wide with long thin petioles. There is a central vein and two parallel secondary veins. Does not have stinging hairs like other nettles.
Flower color
Green; White
Flower value
Showy
Flower form
Insignificant; Spike
Flower size
< 1 inch
Flower detail
Late summer to early fall tiny greenish white wind pollinated flowers appear from the axils of the upper leaves. They form head-like clusters in upward pointing spikes that are 1/2 to 3 inches long. Plants are usually dioecous with male and female plants separate. of the upper leaves. Sometimes the flowers are terminal, but more often they will develop additional leaves beyond the flowers. Male flowers are distributed along the spikes in bunches, while female flowers are produced along the spikes more or less continuously. These flowers are very small and lack petals. There is no floral scent; pollination is by wind.
Bloom time
Fall; Summer
Fruit color
Brown/Copper
Fruit type
Achene
Fruit size
< 1 inch long
Fruit detail
Small, oval-shaped seeds are covered in small, hook-like hairs. Once mature, the seeds are dark brown.
Stem color
Green
Stem detail
Light green round or 4 angled smooth to slightly pubescent stems.
Wildlife & Ecology
Native status
Native
Origin
Canada, central and eastern United States
Distribution
Florida to Texas and west to California, north to Southern Quebec, Southern Ontario and Minnesota. Introduced into France.
Wildlife value
This is a larval host plant that supports Eastern Comma (Polygonia comma), Red Admiral (Vanessa atalanta), and Question Mark Butterfly (Polygonia interrogationis) caterpillars. Questionmark butterflies have an interesting life cycles: overwintered adult Question Mark butterflies lay eggs from spring until the end of May. These will appear as summer adults from May-September, laying eggs that then develop into the winter adult form. The winter adults appear in late August and shelter for the winter starting the cycle all over again. Adult Question Mark butterflies feed on rotting fruit, tree sap, dung, and carrion only visiting flowers for feeding when absolutely necessary. Fly larva (Neolasioptera boehmeriae) form spindle shaped galls on the leaves. Mammals browse the foliage of this plant.
Attracts
Butterflies; Pollinators; Small Mammals
Food & Medicine
Harvest time
Fall
Fruit type
Achene
Landscape Use
Landscape location
Woodland
Landscape theme
Butterfly Garden; Native Garden; Pollinator Garden
Design feature
Border
Garden tags
#wind pollinated #small mammals #food source herbage #eastern comma butterfly #red admiral butterfly #question mark butterfly #larval host plant #butterfly friendly #herbaceous perennial #pollinator plant #wildlife friendly #NC native #native garden #border #pollinator garden #woodland garden
Problems & Resistance
Propagation
Seed

Planted at Hunnicutt

Nobody’s planted this one yet.