When to Plant Yarrow in Douglas County, WA
Yarrow is a drought-tolerant perennial herb with feathery foliage and flat-topped flower clusters in white, yellow, pink, or red. It attracts beneficial insects and is used in herbal medicine.
Douglas County, Washington is in USDA Zone 6b. The average last spring frost is May 8 and the first fall frost is October 4, giving you a growing season of approximately 149 days.
At an elevation of 2,920 feet, Douglas County receives approximately 15.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Yarrow during the growing season. With low rainfall, drip irrigation is essential for growing Yarrow successfully. Mulch heavily to conserve soil moisture.
Douglas County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.2
Drainage
Well Drained
Plant 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 Douglas County
How your county's soil matches Yarrow's growing requirements.
Soil pH
Your soil pH (5.5–6.2) is within Yarrow's preferred range (5.5–7.0).
Soil Texture
The silt loam soil in Douglas County is excellent for Yarrow — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.5%) — Yarrow will thrive.
How to Plant Yarrow
Plant 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 | — | 2.2" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 1.5" | 0" | ❄️ Dormant |
| Apr | — | 1.2" | 0" | ❄️ Dormant |
| May | 2.2" | 0.8" | 1.4" | 🚿 Regular watering |
| Jun | 2.2" | 0.6" | 1.6" | 🚿 Regular watering |
| Jul | 2.2" | 0.2" | 2" | 🚿 Regular watering |
| Aug | 2.2" | 0.3" | 1.9" | 🚿 Regular watering |
| Sep | 2.2" | 0.7" | 1.5" | 🚿 Regular watering |
| Oct | 2.2" | 1.2" | 1" | 💧 Light watering |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 2.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Douglas 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 — Douglas County, WA
Yarrow Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 15 | May 15 – May 29 |
| Harvest | August 14 | Aug 14 – Oct 30 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Only during dry spells
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 5.5–7 · Your soil: ideal
🗺️ USDA Zone
Zone 6b
📆 Growing Season
149 days in Douglas County
Growing Tips for Yarrow in Douglas County
Direct sow Yarrow outdoors after May 08 in Douglas 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.
Douglas County receives only 16" of rain annually. Yarrow needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Direct sow or start from divisions. Yarrow thrives in poor soil and is very drought-tolerant. Deadhead to encourage reblooming. Divide clumps every 3 years.
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 Douglas County, WA?
Douglas County is in Zone 6b with an average last frost of May 8. Plan your Yarrow planting based on this frost date — see the calendar above for exact timing.
What planting zone is Douglas County, WA?
Douglas County, Washington is in USDA Hardiness Zone 6b. The average last spring frost is May 8 and first fall frost is October 4.
Plan Your Garden with Confidence
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