Water regularly during the initial establishment phase. Once established, Achillea tomentosa is highly drought-tolerant. Allow the soil to dry out completely between waterings to prevent root rot.

Overwatering is the most common cause of problems.

Deadhead spent flower stalks regularly to encourage further blooms and maintain a tidy appearance. In late autumn or early spring, cut back the plant by about one-third to one-half to promote dense, vigorous new growth and prevent woody stems.

Achillea tomentosa is easily propagated by division in early spring or autumn. Simply lift the plant, divide the root ball into sections, and replant the divisions.

It can also be propagated from basal cuttings taken in spring.

Achillea tomentosa is a perennial that typically thrives when slightly root-bound. Repotting is rarely necessary.

If the plant becomes overcrowded in a container, it can be divided and repotted in early spring into a slightly larger pot with well-draining soil.