When to Plant Yarrow in Klickitat County, WA
Your May game plan for Klickitat County, Washington
Here's what deserves your attention in Klickitat County, Washington this month. Everything below is tailored to Zone 7b and timed around your local frost dates.
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.
Klickitat County, Washington is in USDA Zone 7b. The average last spring frost is April 14 and the first fall frost is October 19, giving you a growing season of approximately 188 days.
At an elevation of 466 feet, Klickitat County receives approximately 42 inches of rainfall annually with predominantly silt loam soil. Summer highs average 77°F, so choose short-season varieties of Yarrow to ensure they mature before fall.
Klickitat County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-6.8
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 Klickitat County
How your county's soil matches Yarrow's growing requirements.
Soil pH
Your soil pH (5.3–6.8) overlaps with Yarrow's range (5.5–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Klickitat County is excellent for Yarrow — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.7%) — Yarrow will thrive.
How to Plant Yarrow
Plant Water Budget
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 | — | 5.4" | 0" | ❄️ Dormant |
| Feb | — | 4.3" | 0" | ❄️ Dormant |
| Mar | — | 4.4" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 2.6" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| Jul | 2.2" | 0.7" | 1.5" | 🚿 Regular watering |
| Aug | 2.2" | 0.9" | 1.3" | 🚿 Regular watering |
| Sep | 2.2" | 1.6" | 0.6" | 💧 Light watering |
| Oct | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Nov | — | 6.7" | 0" | ❄️ Dormant |
| Dec | — | 6.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Klickitat 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 — Klickitat County, WA
Yarrow Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 21 | Apr 21 – May 5 |
| Harvest | July 21 | Jul 21 – Oct 6 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 5.5–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 7b
📆 Growing Season
188 days in Klickitat County
Growing Tips for Yarrow in Klickitat County
Direct sow Yarrow outdoors after April 14 in Klickitat 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
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 Klickitat County, WA?
Klickitat County is in Zone 7b with an average last frost of April 14. Plan your Yarrow planting based on this frost date — see the calendar above for exact timing.
What planting zone is Klickitat County, WA?
Klickitat County, Washington is in USDA Hardiness Zone 7b. The average last spring frost is April 14 and first fall frost is October 19.
Your Klickitat County Garden Planner — Free
A 24-page printable planner built for Klickitat County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.