When to Plant Chinese Cabbage in Island County, WA
Chinese cabbage (Napa cabbage) forms elongated, barrel-shaped heads with tender, mild-flavored leaves. It is a staple in Asian cooking, particularly for kimchi.
Island County, Washington is in USDA Zone 8a. The average last spring frost is March 30 and the first fall frost is November 3, giving you a growing season of approximately 218 days.
At an elevation of 9 feet, Island County receives approximately 45.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Chinese Cabbage during the growing season.
Island County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-6.7
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 Island County
How your county's soil matches Chinese Cabbage's growing requirements.
Soil pH
Your soil pH (5.6–6.7) overlaps with Chinese Cabbage's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Island County is excellent for Chinese Cabbage — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.3%) — Chinese Cabbage will thrive.
How to Plant Chinese Cabbage
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Chinese Cabbage
Sow every 5.7 weeks. Last sowing by Aug 25 to harvest before frost.
For a dedicated fall crop, sow by Aug 25.
Plant Water Budget
Monthly Watering Guide for Chinese Cabbage
Chinese Cabbage needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Chinese Cabbage Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 6.8" | 0" | ❄️ Dormant |
| Feb | — | 4.7" | 0" | ❄️ Dormant |
| Mar | 6.5" | 4.5" | 2" | 💧 Light watering |
| Apr | 6.5" | 3.7" | 2.8" | 💧 Light watering |
| May | 6.5" | 2.3" | 4.2" | 🚿 Regular watering |
| Jun | 6.5" | 1.6" | 4.9" | 🚿 Regular watering |
| Jul | 6.5" | 0.7" | 5.8" | 🚿 Regular watering |
| Aug | 6.5" | 0.8" | 5.7" | 🚿 Regular watering |
| Sep | 6.5" | 1.6" | 4.9" | 🚿 Regular watering |
| Oct | 6.5" | 4.2" | 2.3" | 💧 Light watering |
| Nov | 6.5" | 7" | 0" | ✅ Rainfall sufficient |
| Dec | — | 7.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Island County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Chinese Cabbage 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.
Chinese Cabbage Planting Timeline — Island County, WA
Chinese Cabbage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 23 | Feb 23 – Mar 9 |
| Transplant Outdoors | March 30 | Mar 30 – Apr 13 |
| Direct Sow | March 16 | Mar 16 – Apr 6 |
| Harvest | May 25 | May 25 – Jun 22 |
| Fall Sowing | August 25 | Aug 25 – Sep 8 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1.5"/week · 1-2 times/week
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 8a
📆 Growing Season
218 days in Island County
Growing Tips for Chinese Cabbage in Island County
Direct sow Chinese Cabbage outdoors after March 30 in Island County when soil has warmed and frost danger has passed.
Common pests for Chinese Cabbage in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Best grown as a fall crop to avoid bolting. Start seeds indoors or direct sow in late summer. Keep soil consistently moist and provide shade in warm weather.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Chinese Cabbage in Other Locations
Frequently Asked Questions
When should I plant Chinese Cabbage in Island County, WA?
Island County is in Zone 8a with an average last frost of March 30. Plan your Chinese Cabbage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Island County, WA?
Island County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is March 30 and first fall frost is November 3.
Plan Your Garden with Confidence
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