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When to Plant Kohlrabi in Washington County, AR

Kohlrabi is an unusual brassica that forms a swollen stem above ground with a mild, sweet turnip-like flavor. Both the bulb and tender leaves are edible.

Washington County, Arkansas is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 24, giving you a growing season of approximately 197 days.

At an elevation of 768 feet, Washington County receives approximately 54.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91ยฐF, providing good warmth for Kohlrabi during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Kohlrabi root diseases.

Washington County, AR (Zone 6b) Moderate season
197 days
Last Spring Frost April 10
197 growing days
First Fall Frost October 24

Washington County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (112 days to spare)
Start indoors: Feb 28 Transplant: Apr 4 🍅 Harvest: May 23 – Jun 27
Recommended (50%) ✓ Fits season (113 days to spare)
Start indoors: Mar 6 Transplant: Apr 10 🍅 Harvest: May 29 – Jul 3
Safe Start (90%) ✓ Fits season (116 days to spare)
Start indoors: Mar 19 Transplant: Apr 23 🍅 Harvest: Jun 11 – Jul 16

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
1.0″/week
Rainfall provides
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Kohlrabi needs ~1,004 GDD — county provides 3,595 GDD Excellent fit

Kohlrabi Planting Timeline โ€” Washington County, AR

Kohlrabi Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 โ€“ Mar 20
Transplant Outdoors April 10 Apr 10 โ€“ Apr 24
Direct Sow March 27 Mar 27 โ€“ Apr 17
Fall Sowing August 15 Aug 15 โ€“ Aug 29
Harvest May 29 May 29 โ€“ Jul 3

Plant 0.5" deep ยท 4" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

45โ€“65 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 6b

Growing Season

197 days

Growing Tips for Washington County

Direct sow in spring or fall. Harvest when bulbs are 2-3 inches in diameter for best texture and flavor. Larger bulbs may become woody and fibrous.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Strawberries

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Frequently Asked Questions

When should I plant Kohlrabi in Washington County, AR?

Washington County is in Zone 6b with an average last frost of April 10. Plan your Kohlrabi planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Washington County, AR?

Washington County, Arkansas is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Washington County gardeners in Zone 6b 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 Washington County, AR. Local conditions may vary. Last updated: April 2026.