What's eating my achillea 'terracotta'?

Achillea 'Terracotta' is a low-maintenance border perennial with strong pest resistance. Aphids are the most frequent problem on tender shoot tips. Spittlebugs leave foamy deposits on stems in early summer. Deer and rabbits rarely graze it — the aromatic, finely divided foliage is unpalatable to most mammalian browsers.

Clusters of small insects on soft new stems and flower buds from late spring; honeydew deposits and mild leaf distortion at growing tips. Remove with a water jet. The flat-topped flower heads of Achillea are excellent for beneficial insects — rely on natural predators and apply soap spray only if needed.

White frothy blobs on stems in May–June, each concealing one sap-feeding nymph; tips of affected stems may wilt slightly but the plant soon grows on. Squeeze out or wash off the spittle and nymph with your fingers or a water jet. No further action needed — it is purely cosmetic and does not spread.

Grazing on young growth at ground level in spring; damage quickly becomes unnoticeable as the plant puts on growth. Scatter ferric phosphate pellets around clumps when shoots emerge. Ensure good drainage as slugs prefer moist, poorly drained soils where yarrows also struggle.