Yarrow – Achillea millefolium

Achillea millefolium is a rhizomatous perennial with finely divided, fern-like leaves. Its flat-topped flower clusters contain many small heads, creating a broader display than a single daisy. Plants can spread by both rhizomes and seed. Sunny, well-drained sites suit the species; wet soil can encourage root problems. The catalogue average is 4000-8000 seeds per gram, a useful reference when comparing bulk quantities.