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When to Plant Napa Cabbage in Grant County, OR

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.

Grant County, Oregon is in USDA Zone 5b. The average last spring frost is June 6 and the first fall frost is September 10, giving you a growing season of approximately 96 days.

At an elevation of 2,838 feet, Grant County receives approximately 22.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Napa Cabbage to ensure they mature before fall.

Grant County, OR (Zone 5b) Very short season
96 days
Last Spring Frost June 6
96 growing days
First Fall Frost September 10

Grant County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 15 Transplant: May 20 🍅 Harvest: Jul 15 – Aug 19
Recommended (50%) ✓ Fits season (5 days to spare)
Start indoors: May 2 Transplant: Jun 6 🍅 Harvest: Aug 1 – Sep 5
Safe Start (90%) ✓ Fits season (9 days to spare)
Start indoors: May 22 Transplant: Jun 26 🍅 Harvest: Aug 21 – Sep 25

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.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
1.0″/week
You supply
1.0″/week
Watering frequency 2-3 times/week
Season total 821 gal / 100 sq ft
Napa Cabbage needs ~796 GDD — county provides 1,176 GDD Excellent fit

Napa Cabbage Planting Timeline โ€” Grant County, OR

Napa Cabbage Planting Calendar

Activity When Date Range
Start Indoors May 2 May 2 โ€“ May 16
Transplant Outdoors June 6 Jun 6 โ€“ Jun 20
Direct Sow May 23 May 23 โ€“ Jun 13
Fall Sowing July 2 Jul 2 โ€“ Jul 16
Harvest August 1 Aug 1 โ€“ Sep 5

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

High โ€” keep soil consistently moist

Days to Maturity

55โ€“75 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 5b

Growing Season

96 days

Growing Tips for Grant County

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

  • Strawberries

Level Up Your Garden

Frequently Asked Questions

When should I plant Napa Cabbage in Grant County, OR?

Grant County is in Zone 5b with an average last frost of June 6. Plan your Napa Cabbage planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Grant County, OR?

Grant County, Oregon is in USDA Hardiness Zone 5b. The average last spring frost is June 6 and first fall frost is September 10.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Grant County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

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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 Grant County, OR. Local conditions may vary. Last updated: April 2026.