Science · Plants, Natives & Crops
Yarrow
Flat-topped flowers and finely divided foliage; local native material and ornamental colored cultivars differ in origin and growth.
Achillea millefolium species complex and cultivars · Rhizomatous herbaceous perennial
Profile
- Light
- Full sun for compact growth
- Habit
- Spreading perennial, commonly 1–3 ft in flower
- Soil
- Well-drained soil; rich wet ground encourages lodging
- Maintenance
- Deadhead or cut back after bloom; manage spreading clumps
Water & soil targets
- Moisture (VWC)
- Site-calibrated; depends on soil texture
- Salinity tolerance
- Not reliably characterized for this catalog label; avoid saline irrigation and diagnose with soil/water testing.
- Drought tolerance
- Good once established, though appearance improves with occasional water.
Optimal root measurement depth
3–8 in
Shallow fibrous or rhizomatous roots. Typical guidance; confirm with a soil probe on site.
Deep occasional irrigation with drying intervals; avoid persistently wet crowns and adjust for cultivar and soil.
Problems to watch
- Powdery mildew
- Root rot in wet soil
- Flopping from shade or excess fertility
Stress signs
- White powder on foliage
- Blackened rotting crown
- Weak elongated stems and lodging
Where you'll find it
- Pollinator border
- Low-water meadow or groundcover
More plants, natives & crops
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All Science profilesGeneral agronomic guidance and typical ranges; actual targets vary by site, soil, climate and season.