Roundleaf Thoroughwort is known for its umbels filled with clusters of white flowers, frequently visited by flying insects including wasps, butterflies, and bees. Wasps are helpful in the garden in keeping pest insects at bay. This upright perennial grows in bogs, savannahs, and wooded areas. Although it can occur in wetlands, it commonly appears in non-wetlands as well. Differing from other Eupatorium species, this plant has grey to silvery green leaves. The species epithet “rotundifolium” derives from the rotund appearance of the leaves. Roundleaf Thoroughwort can hybridize with other Eupatorium species if they are blooming at the same time. Although reported to be drought tolerant, leaves can scorch in long periods of drought. Providing water at such times can prevent this. In winter, this plant will appear to have died all the way to the ground. If you are adding new plantings to the area, having their locations labeled can prevent them from accidentally being dug up. The following spring, a rosette will form on the ground, followed by this plant growing upright through the growing season.
