When to plant Yarrow in Harper County County,
Aim to plant Yarrow in Harper County County on or after April 9; the window stays open through April 30. Harper County County's 201-day frost-free season gives you enough for a full main crop and a short fall succession.
When to Plant Yarrow in Harper County, KS
Top priorities for Harper County, Kansas gardeners in June
June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Harper County, Kansas.
-
Start yarrow under lights
Starting these indoors now means sturdy transplants ready the moment your soil warms up.
-
Collect yarrow at their peak
If you can't use it all right away, check the food-preservation section of your planner.
A few tasks this June that'll pay off in July
- First harvests: yarrow
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.
Harper County, Kansas is in USDA Zone 7a. The average last spring frost is April 9 and the first fall frost is October 27, giving you a growing season of approximately 201 days.
At an elevation of 745 feet, Harper County receives approximately 27.7 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Yarrow during the growing season.
Harper County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.8
Drainage
Well Drained
Yarrow Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Harper County
How your county's soil matches Yarrow's growing requirements.
Soil pH
Your soil pH (6.2–7.8) overlaps with Yarrow's range (5.5–7.0), though not a perfect match.
Soil Texture
The loam soil in Harper County is excellent for Yarrow — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Yarrow.
Organic Matter
Organic matter is excellent (4.1%) — Yarrow will thrive.
How to Plant Yarrow
Succession Planting Yarrow
Sow every 6.9 weeks. Last sowing by Jul 29 to harvest before frost.
Yarrow Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Yarrow
Yarrow needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Yarrow Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.7" | 0" | ❄️ Dormant |
| Feb | — | 1.1" | 0" | ❄️ Dormant |
| Mar | — | 1.6" | 0" | ❄️ Dormant |
| Apr | 2.2" | 2.6" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.7" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| Nov | — | 1" | 0" | ❄️ Dormant |
| Dec | — | 0.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Harper County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Yarrow Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Yarrow Planting Timeline — Harper County, KS
Yarrow Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 5 | Feb 5 – Feb 19 |
| Transplant Outdoors | April 16 | Apr 16 – Apr 30 |
| Direct Sow | April 9 | Apr 9 – Apr 30 |
| Bloom | June 18 | Jun 18 – Oct 29 |
· 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Only during dry spells
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 5.5–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
201 days in Harper County
Growing Tips for Yarrow in Harper County
Direct sow Yarrow outdoors after April 09 in Harper County when soil has warmed and frost danger has passed.
Common pests for Yarrow in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
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 Harper County, KS?
Harper County is in Zone 7a with an average last frost of April 9. Plan your Yarrow planting based on this frost date — see the calendar above for exact timing.
What planting zone is Harper County, KS?
Harper County, Kansas is in USDA Hardiness Zone 7a. The average last spring frost is April 9 and first fall frost is October 27.
When should I plant Yarrow in Harper County, ?
In Harper County, , plant Yarrow after the last frost (around April 9) and before the first frost (around October 27). Best results when soil holds above 50°F.
What growing zone is Harper County, for Yarrow?
Harper County sits in USDA Zone 7a. Yarrow grows reliably in zones 3a through 9b, so it's a good fit here.
Can Yarrow grow in Harper County's climate?
Yes — Yarrow grows well in Harper County's temperate climate. Harper County averages a 201-day frost-free season, with last frost around April 9 and first frost around October 27.
Your Harper County Garden Planner — Free
A 22-page printable planner built for Harper County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.