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When to Plant Chinese Cabbage in Jefferson 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.

Jefferson County, Washington is in USDA Zone 8a. The average last spring frost is April 14 and the first fall frost is October 29, giving you a growing season of approximately 198 days.

At an elevation of 205 feet, Jefferson County receives approximately 40.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Chinese Cabbage during the growing season.

Jefferson County, WA (Zone 8a) Moderate season
198 days
Last Spring Frost April 14
198 growing days
First Fall Frost October 29

Jefferson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (116 days to spare)
Start indoors: Mar 2 Transplant: Apr 6 🍅 Harvest: Jun 1 – Jun 29
Recommended (50%) ✓ Fits season (114 days to spare)
Start indoors: Mar 10 Transplant: Apr 14 🍅 Harvest: Jun 9 – Jul 7
Safe Start (90%) ✓ Fits season (110 days to spare)
Start indoors: Apr 4 Transplant: May 9 🍅 Harvest: Jul 4 – Aug 1

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 Jefferson County

How your county's soil matches Chinese Cabbage's growing requirements.

Soil pH

Your soil pH (5.7โ€“6.8) overlaps with Chinese Cabbage's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The silt loam soil in Jefferson County is excellent for Chinese Cabbage โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Chinese Cabbage is a heavy drinker but your soil drains very quickly. Mulch heavily and consider drip irrigation.

Organic Matter

Organic matter is excellent (5.7%) โ€” Chinese Cabbage will thrive.

How to Plant Chinese Cabbage

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Chinese Cabbage

4
successive plantings in your 198-day season

Sow every 5.7 weeks. Last sowing by Aug 20 to harvest before frost.

For a dedicated fall crop, sow by Aug 20.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.9″/week
You supply
1.1″/week
Watering frequency 2-3 times/week
Season total 1,915 gal / 100 sq ft

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 โ€” 6.4" 0" โ„๏ธ Dormant
Feb โ€” 4.7" 0" โ„๏ธ Dormant
Mar โ€” 3.9" 0" โ„๏ธ Dormant
Apr 6.5" 2.6" 3.9" ๐Ÿšฟ Regular watering
May 6.5" 2.1" 4.4" ๐Ÿšฟ Regular watering
Jun 6.5" 1.5" 5" ๐Ÿšฟ Regular watering
Jul 6.5" 0.5" 6" ๐Ÿšฟ Regular watering
Aug 6.5" 0.6" 5.9" ๐Ÿšฟ Regular watering
Sep 6.5" 1.6" 4.9" ๐Ÿšฟ Regular watering
Oct 6.5" 3.5" 3" ๐Ÿ’ง Light watering
Nov โ€” 6.3" 0" โ„๏ธ Dormant
Dec โ€” 7.1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Jefferson County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 needs ~960 GDD — county provides 3,168 GDD Excellent fit

Chinese Cabbage Planting Timeline โ€” Jefferson County, WA

Chinese Cabbage Planting Calendar

Activity When Date Range
Start Indoors March 10 Mar 10 โ€“ Mar 24
Transplant Outdoors April 14 Apr 14 โ€“ Apr 28
Direct Sow March 31 Mar 31 โ€“ Apr 21
Harvest June 9 Jun 9 โ€“ Jul 7
Fall Sowing August 20 Aug 20 โ€“ Sep 3

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May โ€”
June Harvest
July Harvest
August Fall Sowing
September Fall Sowing
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1.5"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

50โ€“70 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

198 days in Jefferson County

Growing Tips for Chinese Cabbage in Jefferson County

Direct sow Chinese Cabbage outdoors after April 14 in Jefferson 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

  • Strawberries
  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Chinese Cabbage in Jefferson County, WA?

Jefferson County is in Zone 8a with an average last frost of April 14. Plan your Chinese Cabbage planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Jefferson County, WA?

Jefferson County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is April 14 and first fall frost is October 29.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Jefferson County gardeners in Zone 8a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Jefferson County, WA. Local conditions may vary. Last updated: April 2026.