When to Plant Strawberries in King County, WA
May in the garden — King County, Washington
Your garden in King County, Washington is working on a schedule, even when you're not. Here's where you should be this May.
Strawberries are a beloved perennial fruit available as June-bearing, ever-bearing, and day-neutral types. They are one of the easiest fruits to grow in containers or garden beds.
King County, Washington is in USDA Zone 9a. The average last spring frost is April 7 and the first fall frost is October 30, giving you a growing season of approximately 206 days.
At an elevation of 258 feet, King County receives approximately 37.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Strawberries during the growing season.
King County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-6.4
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 King County
How your county's soil matches Strawberries's growing requirements.
Soil pH
Your soil pH (5.7–6.4) is within Strawberries's preferred range (5.5–6.8).
Soil Texture
The silt loam soil in King County is excellent for Strawberries — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.5%) — Strawberries will thrive.
How to Plant Strawberries
How Much Strawberries to Grow
For a family of 4, plant approximately 40 strawberries plants in about 80 sq ft. In King County's 206-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Plant Water Budget
Monthly Watering Guide for Strawberries
Strawberries needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Strawberries Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5.9" | 0" | ❄️ Dormant |
| Feb | — | 4.5" | 0" | ❄️ Dormant |
| Mar | — | 3.4" | 0" | ❄️ Dormant |
| Apr | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| May | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Jun | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Jul | 4.3" | 0.6" | 3.7" | 🚿 Regular watering |
| Aug | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Sep | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Oct | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Nov | — | 5.6" | 0" | ❄️ Dormant |
| Dec | — | 5.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in King County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Strawberries 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.
Strawberries Planting Timeline — King County, WA
Strawberries Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 21 | Apr 21 – May 5 |
| Harvest | July 21 | Jul 21 – Feb 16 |
· 12" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Harvest |
| February | Harvest |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| December | Harvest |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
90–365 days
🧪 Soil pH
Needs 5.5–6.8 · Your soil: ideal
🗺️ USDA Zone
Zone 9a
📆 Growing Season
206 days in King County
Growing Tips for Strawberries in King County
Direct sow Strawberries outdoors after April 07 in King County when soil has warmed and frost danger has passed.
Your 206.0-day growing season in King County is tight for Strawberries (90.0-365.0 days to maturity). Start indoors and choose early-maturing varieties.
General growing tips
Plant with crowns at soil level. Remove runners the first year to strengthen plants. Mulch with straw to keep fruit clean and suppress weeds. Renovate June-bearing beds after harvest.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Strawberries in Other Locations
Frequently Asked Questions
When should I plant Strawberries in King County, WA?
King County is in Zone 9a with an average last frost of April 7. Plan your Strawberries planting based on this frost date — see the calendar above for exact timing.
What planting zone is King County, WA?
King County, Washington is in USDA Hardiness Zone 9a. The average last spring frost is April 7 and first fall frost is October 30.
Your King County Garden Planner — Free
A 24-page printable planner built for King County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.