White Vervain

Verbena urticifolia greets you with a fireworks explosion of flowers that are tinier than those of its cousin, blue vervain. White vervain’s flowers open on clusters along the lengths of flower spikes arising from the top of the central stem, branching out in all directions. Spikes are about 6″ long, and the delicate 5-petaled flowers are only 1/8″ across. With only a few flowers open at a time, the effect lends a delicate airiness to the whole display. Plants can grow to 4′ and even 5′ tall.

In contrast to blue vervain, white vervain leaves are wider at up to 2.5″ and up to 6″ long. Hairy and soft, the leaves are oppositely attached on their small stalks, are coarsely toothed, and taper to a sharp point.

White vervain plants reproduce by re-seeding themselves.

https://www.illinoiswildflowers.info/savanna/plants/wh_vervain.htm