Hill yarrow (Achillea collina): complete guide

Achillea collina, commonly known as hill yarrow or hügel-schafgarbe, is a versatile perennial from Central Europe. Native to grasslands, hillsides, and semi-dry habitats in Poland, Hungary, and eastern Switzerland, it thrives under modest conditions. For gardens, it offers a robust, low-maintenance option with rich flower colours throughout summer months.

Overview

Achillea collina forms a well-branched, compact perennial mound, typically 30-50 centimetres tall. Growth is rapid but orderly, producing continuous floral displays from May through September. Colour ranges from pink to purple-pink, sometimes warm orange-pink tones depending on cultivar selection. This is a plant for those seeking colour without constant fussing.

Appearance & bloom

Foliage is finely divided, feathery, grey-green. Not as refined as some relatives, but ornamental nonetheless. Flower clusters are flat, compound umbels, typically pink to purple tones, sometimes warmer orange-pink. Blooming can extend two months with regular removal of spent flowers. Yellow stamens add visual interest. Fresh flowers emerge continuously if deadheaded.

Ideal location

Full sun is essential; minimum 6 hours direct daily sunlight. Light shade is tolerated but flower production diminishes. This is a plant that dislikes deep shade.

Soil

Achillea collina grows in virtually any well-draining soil. Heavy clay should be lightly amended with sand. Fertility is not critical; poor, lean soils are well tolerated. Water drainage is important; waterlogging invites fungal disease.

Watering

After planting, water regularly to establish roots. Established plants tolerate drought well and need little supplemental watering. In extremely dry years, occasional irrigation boosts flower production.

Pruning

Regularly remove spent flowers (weekly during bloom season) to stimulate continuous flowering. Cut back in autumn to 15-20 centimetres to promote compact growth in spring.

Maintenance calendar

• Spring: Clean plant, remove old stems.
• Summer: Deadhead continuously, water during drought.
• Autumn: Cut back to 15-20cm, prepare for winter.
• Winter: No maintenance; plant fully hardy.

Winter hardiness

Achillea collina is hardy in USDA zones 3-8, surviving -30 degrees Celsius or lower. Winter hardiness is not a concern in Northern Europe.

Companion plants

Pairs well with: Salvia x sylvestris, Delphinium species, Lupinus hybrida, Campanula persicifolia. Also: Coreopsis, Echinacea, lavender species.

Closing

Hill yarrow is a reliable perennial for sunny borders. Less refined than some relatives but more robust. Readily available at garden centres. GardenWorld recommends this plant for those seeking durable colour and proven frost hardiness without constant coddling.