Hoary Vervain is a North American native wildflower in the verbena family and is sparsely found on the coast of NC but is abundant in the central part of the USA. It is found in prairies, thickets, fields and is drought tolerant, preferring medium to dry sandy, rocky or clay soils with good drainage. Hoary Vervain is a clump-forming plant that naturalizes by self-seeding so deadhead to control spread if desired. When started from seed, it blooms in the second year, attracting butterflies and bees to its spikes of blue-purple (rarely pink) flowers. The leaves, stems and flowers have hairs giving it its common names. Plant in full sun in well-drained soils and don't overwater. Use in a dry sunny location, in a rock garden or naturalized settings as prairies or meadows.
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 sun (6 or more hours of direct sunlight a day)
Soil texture
Clay; Sand; Shallow Rocky
Soil drainage
Good Drainage | Occasionally Dry
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 2 ft. 0 in. - 4 ft. 0 in. | Width: 1 ft. 6 in. - 2 ft. 0 in.
Growth rate
Medium
Maintenance
Low
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Habit / form
Erect
Leaf color
Gray/Silver; Green
Leaf type
Simple
Leaf arrangement
Opposite
Leaf shape
Obovate; Ovate
Leaf margin
Serrate
Leaf size
3-6 inches long, 1-3 inches wide
Hairs present
Yes
Leaf detail
4 inches long and 3 inches across oval to obovate coarsely-toothed leaves are usually stalkless and covered with whitish hairs giving it a gray-green appearance. Leaves have pinnate venation and also a reticulated network of smaller veins.
Flower color
Blue; Purple/Lavender
Flower value
Long Bloom Season; Showy
Flower form
Panicle; Spike
Flower shape
Star
Flower size
< 1 inch
Flower detail
Pink or blue-purple flowers that bloom from bottom to top of hairy, narrow, upright spikes up to 8 inches long. Individual flowers are 1/4 inch across and have 5 petals. Only a few are open at a time. Blooms for 6 weeks in mid to late summer.
Bloom time
Summer
Fruit color
Brown/Copper
Fruit type
Nut
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
Four brown nutlets are produced per flower.
Stem color
Green; Purple/Lavender; Red/Burgundy
Stem detail
Green to reddish stems have long white hairs
Wildlife & Ecology
Native status
Native
Origin
North America
Distribution
AL , AR , AZ , CO , CT , DE , GA , IA , ID , IL , IN , KS , KY , MA , MI , MN , MO , MS , MT , NC , ND , NE , NJ , NM , NV , NY , OH , OK , PA , SD , TN , TX , UT , VT , WA , WI , WV , WY Canada: ON
Wildlife value
Host plant for common buckeye butterfly and others. Various pollinators are attracted to the plant. Birds and small mammals will eat the seeds.