Virtues: We love culver's root (Veronicastrum virginicum) for its tall spikes of white or purple flowers that begin in early or midsummer and can continue until autumn. Veronicastrum is a USA-native perennial good at attracting butterflies and bees.
Common name: Culver's root
Botanical name:Veronicastrum virginicum
Flowers: Small tube-shaped flowers line long, slim flower stems and open from the top of the stem downward in warm weather. Smaller flower stems can develop at the sides, giving a candelabra structure. Bloom can run from late spring to autumn, though midsummer to autumn is more typical. Flowers are white or purple, depending on variety, of which there are several.
Foliage: Long, narrow leaves line the bottom portions of the stems.
Habit: Culver's root is an herbaceous perennial that grows four to seven feet tall and about half as wide. It dies back to the ground in fall.
Season: Mid- through late summer, for its flowers. In some climates it can begin flowering as early as late spring.
Origin: Native to damp prairies, open woods and stream banks of the eastern half of North America.
How to grow Veronicastrum virginicum: Grow culver's root in full sun with regular watering. It can tolerate wet soil, making it a good choice for a poorly drained area of the yard or for inclusion in a rain garden. In very hot areas of the Deep South, veronicastrums need some light shade in the afternoon. They can take a few years to become established, but then they are low maintenance as long as they receive ample water. USDA Zones 3–8.