Achillea setacea prefers well-drained soil and is drought-tolerant once established. Water moderately during dry spells, allowing the soil to dry out between waterings.

Overwatering can lead to root rot, so ensure good drainage, especially in containers. Reduce watering in winter.

Deadhead spent flower stalks regularly to encourage continuous blooming and maintain a tidy appearance. Cut back the entire plant to the ground in late autumn or early spring to promote vigorous new growth.

Remove any dead or diseased foliage promptly to prevent spread.

Achillea setacea is easily propagated by division in early spring or autumn. Simply dig up a mature clump and divide it into smaller sections, ensuring each piece has roots and shoots.

It can also be grown from seed sown in spring, either directly outdoors or started indoors.

Established Achillea setacea plants generally do not require frequent repotting, especially when planted in the ground.

If grown in containers, repot every 2-3 years in spring or autumn into a slightly larger pot with fresh, well-draining potting mix. This helps refresh the soil and provides more space.