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When to Plant Radish in Grant County, OK

Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.

Grant County, Oklahoma is in USDA Zone 6b. The average last spring frost is April 11 and the first fall frost is October 27, giving you a growing season of approximately 199 days.

At an elevation of 564 feet, Grant County receives approximately 25.7 inches of rainfall annually with predominantly loam soil. Summer highs average 89ยฐF, providing good warmth for Radish during the growing season.

Grant County, OK (Zone 6b) Moderate season
199 days
Last Spring Frost April 11
199 growing days
First Fall Frost October 27

Grant County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (154 days to spare)
Transplant: Apr 3 🍅 Harvest: May 1 – May 22
Recommended (50%) ✓ Fits season (150 days to spare)
Transplant: Apr 11 🍅 Harvest: May 9 – May 30
Safe Start (90%) ✓ Fits season (155 days to spare)
Transplant: Apr 23 🍅 Harvest: May 21 – Jun 11

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
0.5″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 973 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Radish needs ~477 GDD — county provides 3,333 GDD Excellent fit

Radish Planting Timeline โ€” Grant County, OK

Radish Planting Calendar

Activity When Date Range
Direct Sow March 28 Mar 28 โ€“ Apr 18
Fall Sowing August 18 Aug 18 โ€“ Sep 1
Harvest April 25 Apr 25 โ€“ May 16

Plant 0.5" deep ยท 2" apart ยท Rows 6" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

22โ€“35 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6b

Growing Season

199 days

Growing Tips for Grant County

Direct sow every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.

Companion Planting

Good Companions

Avoid Planting Near

  • Hyssop

Level Up Your Garden

Frequently Asked Questions

When should I plant Radish in Grant County, OK?

Grant County is in Zone 6b with an average last frost of April 11. Plan your Radish planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Grant County, OK?

Grant County, Oklahoma is in USDA Hardiness Zone 6b. The average last spring frost is April 11 and first fall frost is October 27.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Grant 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 Grant County, OK. Local conditions may vary. Last updated: April 2026.