When to Plant Napa Cabbage in Kitsap County, WA
This month in Kitsap County, Washington
Your Kitsap County, Washington garden is entering a new phase. Here's what's on the schedule for April and why each task matters now.
-
Start napa cabbage indoors
A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.
Looking ahead to May
- First harvests: napa cabbage
Napa cabbage forms tall, barrel-shaped heads with tender, crinkled leaves and a mild, slightly sweet flavor. It is the primary cabbage used for kimchi.
Kitsap County, Washington is in USDA Zone 8a. The average last spring frost is March 25 and the first fall frost is November 5, giving you a growing season of approximately 225 days.
At an elevation of 264 feet, Kitsap County receives approximately 38 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Napa Cabbage during the growing season.
Kitsap County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-6.3
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 Kitsap County
How your county's soil matches Napa Cabbage's growing requirements.
Soil pH
Your soil pH (5.3–6.3) is more acidic than Napa Cabbage prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Kitsap County is excellent for Napa Cabbage — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.5%) — Napa Cabbage will thrive.
How to Plant Napa Cabbage
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Napa Cabbage
Sow every 6.3 weeks. Last sowing by Aug 22 to harvest before frost.
For a dedicated fall crop, sow by Sep 10.
Plant Water Budget
Monthly Watering Guide for Napa Cabbage
Napa 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 | Napa Cabbage Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5.1" | 0" | ❄️ Dormant |
| Feb | — | 4.5" | 0" | ❄️ Dormant |
| Mar | 6.5" | 4.3" | 2.2" | 💧 Light watering |
| Apr | 6.5" | 2.7" | 3.8" | 🚿 Regular watering |
| May | 6.5" | 2" | 4.5" | 🚿 Regular watering |
| Jun | 6.5" | 1.3" | 5.2" | 🚿 Regular watering |
| Jul | 6.5" | 0.7" | 5.8" | 🚿 Regular watering |
| Aug | 6.5" | 0.7" | 5.8" | 🚿 Regular watering |
| Sep | 6.5" | 1.4" | 5.1" | 🚿 Regular watering |
| Oct | 6.5" | 2.9" | 3.6" | 🚿 Regular watering |
| Nov | 6.5" | 6.5" | 0" | ✅ Rainfall sufficient |
| Dec | — | 6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Kitsap County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Napa 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.
Napa Cabbage Planting Timeline — Kitsap County, WA
Napa Cabbage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 18 | Feb 18 – Mar 4 |
| Transplant Outdoors | March 25 | Mar 25 – Apr 8 |
| Direct Sow | March 11 | Mar 11 – Apr 1 |
| Harvest | May 20 | May 20 – Jun 24 |
| Fall Sowing | August 27 | Aug 27 – Sep 10 |
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 · 2-3 times/week
📅 Days to Maturity
55–75 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 8a
📆 Growing Season
225 days in Kitsap County
Growing Tips for Napa Cabbage in Kitsap County
Direct sow Napa Cabbage outdoors after March 25 in Kitsap County when soil has warmed and frost danger has passed.
Common pests for Napa 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. Direct sow in late summer, 60-70 days before first frost. Keep soil evenly moist. Bolt-resistant varieties are available for spring planting.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Napa Cabbage in Other Locations
Frequently Asked Questions
When should I plant Napa Cabbage in Kitsap County, WA?
Kitsap County is in Zone 8a with an average last frost of March 25. Plan your Napa Cabbage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Kitsap County, WA?
Kitsap County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is March 25 and first fall frost is November 5.
Your Kitsap County Garden Planner — Free
A 24-page printable planner built for Kitsap County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.