When to plant Yarrow in Cooper County, MO
The best window to plant Yarrow in Cooper County, is April 10–May 1, when soil warms to 50°F. Last frost typically hits April 10; first frost October 25.
When to Plant Yarrow in Cooper County, MO
Achillea millefolium (Yarrow) is a tough, drought-tolerant native perennial with aromatic finely-divided foliage and broad flat-topped flower clusters that serve as a landing platform for hundreds of beneficial insect species. Available in white (the species type) and a wide range of cultivars spanning yellow, gold, pink, salmon, and deep red. Spreads by rhizome to form ground-covering colonies; blooms from late spring through midsummer with reblooming into fall if deadheaded. Exceptional in hot, dry sites where other perennials fail.
Cooper County, Missouri is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 25, giving you a growing season of approximately 198 days.
At an elevation of 1,035 feet, Cooper County receives approximately 35.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Yarrow during the growing season.
Cooper County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.7
Drainage
Well Drained
Monthly Watering Guide for Yarrow
Yarrow needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Yarrow Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3" | 1.3" | 💧 Light watering |
| May | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Sep | 4.3" | 3" | 1.3" | 💧 Light watering |
| Oct | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 1.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Cooper County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Yarrow Planting Timeline — Cooper County, MO
Yarrow Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 6 | Feb 6 – Feb 20 |
| Transplant Outdoors | April 17 | Apr 17 – May 1 |
| Direct Sow | April 10 | Apr 10 – May 1 |
| Bloom | June 26 | Jun 26 – Oct 23 |
· 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 5.5–7 · Your soil: N/A
🗺️ USDA Zone
Zone 6b
📆 Growing Season
198 days in Cooper County
Growing Tips for Cooper County
Start seeds indoors 8–10 weeks before last frost; seeds need light for germination — press onto soil surface, do not cover. Direct sow after last frost or divide established clumps in spring or fall. Thrives in poor, well-drained soil — rich soil and high fertility cause floppy stems and reduce flower count. Avoid overwatering; excellent drought tolerance once established. Deadhead spent clusters to encourage rebloom. Divide every 2–3 years to prevent center die-out and control spread. Year 2+ plants bloom most heavily; first-year plants may produce limited flowers. Dried flowers retain color well for arrangements.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Yarrow in Other Locations
Frequently Asked Questions
When should I plant Yarrow in Cooper County, MO?
Cooper County is in Zone 6b with an average last frost of April 10. Plan your Yarrow planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cooper County, MO?
Cooper County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 25.
When should I plant Yarrow in Cooper County, MO?
In Cooper County, MO, plant Yarrow after the last frost (around April 10) and before the first frost (around October 25). Best results when soil holds above 50°F.
What growing zone is Cooper County, MO for Yarrow?
Cooper County sits in USDA Zone 6b. Yarrow grows reliably in zones 3a through 9b, so it's a good fit here.
Can Yarrow grow in Cooper County's climate?
Yes — Yarrow grows well in Cooper County's temperate climate. Cooper County averages a 198-day frost-free season, with last frost around April 10 and first frost around October 25.
Your Cooper County Garden Planner — Free
A 22-page printable planner built for Cooper County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.