Bristly Yarrow

Woolly Yarrow should be watered moderately and regularly, about once or twice per week, to keep the soil evenly moist. When watering, be sure to avoid getting water on the leaves, as this can cause leaf rot. Avoid overwatering, since it can cause root rot. Salt buildup can also be a problem, so it's best to use softened or distilled water when possible. If you allow the soil to dry out completely between waterings, it will encourage the plant to form new roots.

Woolly Yarrow is a cold-hardy perennial that typically prefers full sun and benefits from 6-8 hours of direct sunlight each day. In summer, when the sun is at its strongest, the plant may even fare better with a bit of midday shade to protect it from heat stress. In shadier parts of the garden, planting in late summer will help ensure that Woolly Yarrow gets enough sun by the time winter arrives. In areas with long summer days, Woolly Yarrow can tolerate full sun without any damage. While creative gardeners may be able to coax Woolly Yarrow to grow in partial shade, the plants will likely not produce as many flowers as they would with more sunlight.

Woolly Yarrow should be pruned in the late winter/early spring, before the new growth emerges. Pruning should be done in moderation as this species prefers being slightly overgrown. Remove any dead branches, stems, and wilting foliage, but avoid removing more than 1-third of the plant's foliage. Doing so may result in a weaker or dying plant. To shape the plant, simply clip outward facing stems just above a leaf bud; this will encourage the plant to produce new growth.