Achillea lewisii
Achillea lewisii · Asteraceae
The gardener's calendar
Ideal time to plant achillea lewisii: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Foliage
- Deciduous, finely cut and aromatic
- Flowering
- June to August, pale yellow flowers in corymbs
- Mature size
- 40 cm tall, compact and bushy habit
- Growth
- Fast and vigorous
- Hardiness
- Excellent, down to -15°C
- Origin
- Mountainous regions of North America
- Soil type
- Well-drained, rocky, rather poor
✓ Taxonomy verifiedSource: AI estimate · hardiness: reliability low.
Expert tips
The key tip
Achillea lewisii thrives in poor, well-drained soil; water regularly during the first year, then leave it dry. In rich or overly wet soil, it spreads, weakens, and flowers poorly.
The common mistake
Overwatering or planting it in fertile soil: it becomes soft, flops over, and flowering decreases.
The pro's trick
Divide clumps every 3-4 years in April to prevent the center from hollowing out.
Care
Sunlight
Lewis' yarrow needs full sun to thrive. Place it in a sunny spot with at least 6 hours of direct light per day. Lack of light weakens the plant and limits flowering.
Watering
A very frugal plant, it tolerates drought well once established. Water moderately when planting, then gradually reduce watering. During extended summer periods, occasional watering is enough. Let the soil dry between waterings.
Soil and planting
Prefer well-drained, rocky or sandy soil, even poor soil. Avoid heavy and wet soils that promote root rot. Improve drainage with gravel or coarse sand if necessary.
Pruning and maintenance
Remove faded flowers regularly to extend flowering. In autumn or late winter, cut the clump back to ground level or 10 cm high to rejuvenate the plant. This species doesn't require complex pruning.
Fertilizing
Lewis' yarrow thrives in poor soils and needs virtually no fertilizer. A light mineral application in spring may suffice; too much fertilizing weakens hardiness and encourages soft foliage.
Health and pests
Very hardy, it mainly fears excessive moisture causing rot. Powdery mildew can appear in warm, humid conditions. Ensure good air circulation and avoid watering in late afternoon to prevent fungal problems.
Did you know?
Yarrow gets its name from the Greek hero Achilles, who supposedly used it to heal his warriors' wounds. The Achillea genus was long renowned for its healing properties in traditional medicine. Lewis' yarrow, an alpine species from the Rocky Mountains, symbolizes resilience: it colonizes the most hostile rocky slopes and flowers generously without asking for almost anything in return.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
Add this plant to my garden →Plants from the same family
- SunflowerHelianthus annuus
- YarrowAchillea millefolium
- Ox-eye daisyLeucanthemum vulgare
- SneezewortAchillea ptarmica
- Canadian goldenrodSolidago canadensis
- WormwoodArtemisia absinthium
Tips generated and checked by Viridia — adapt them to your local climate.