Heal-all can be identified by its square stems that are hairy when young and become smooth as the plant ages. Its leaf blades grow opposite each other and are sparsely hairy, though sometimes smooth. Heal-all also features creeping stems that root freely at the nodes, producing a shallow but aggressive fibrous root system. This broadleaf weed reproduces by seeds. In bloom, Heal-all features dark-violet to purple-colored flowers that raise in a 1/2-inch terminal spike.
This broadleaf weed grows in dense patches in grasslands, lawns and wood clearings. It thrives in grassy areas and can be especially aggressive in open areas of grass. Heal-all can be found throughout much of the continental United States.
Prunella vulgaris can be difficult to get rid of using cultural weed control methods alone because this broadleaf weed can usually grow beneath mowing levels that are safe for your lawn. Additionally, disturbed areas seeing heavy foot traffic actually encourage Heal-all growth because the creeping stems root at the nodes when they touch the ground.