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When to Plant Turnip in Harmon County, OK

Turnips are a fast-growing cool-season root vegetable with edible roots and greens. Baby turnips are sweet and tender while mature ones are more pungent.

Harmon County, Oklahoma is in USDA Zone 7b. The average last spring frost is March 31 and the first fall frost is November 5, giving you a growing season of approximately 219 days.

At an elevation of 993 feet, Harmon County receives approximately 34.4 inches of rainfall annually with predominantly loam soil. Summer highs average 91ยฐF, providing good warmth for Turnip during the growing season.

Harmon County, OK (Zone 7b) Long season
219 days
Last Spring Frost March 31
219 growing days
First Fall Frost November 5

Harmon County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (142 days to spare)
Transplant: Mar 23 🍅 Harvest: May 4 – Jun 8
Recommended (50%) ✓ Fits season (142 days to spare)
Transplant: Mar 31 🍅 Harvest: May 12 – Jun 16
Safe Start (90%) ✓ Fits season (142 days to spare)
Transplant: Apr 15 🍅 Harvest: May 27 – Jul 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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 796 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Turnip needs ~912 GDD — county provides 3,996 GDD Excellent fit

Turnip Planting Timeline โ€” Harmon County, OK

Turnip Planting Calendar

Activity When Date Range
Direct Sow March 17 Mar 17 โ€“ Apr 7
Fall Sowing August 27 Aug 27 โ€“ Sep 10
Harvest April 28 Apr 28 โ€“ Jun 2

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Direct Sow
April Direct Sow Harvest
May Harvest
June Harvest
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

40โ€“60 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 7b

Growing Season

219 days

Growing Tips for Harmon County

Direct sow in early spring or late summer. Harvest when roots are 2-3 inches in diameter for best flavor. Both the roots and the greens are nutritious and edible.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Level Up Your Garden

Frequently Asked Questions

When should I plant Turnip in Harmon County, OK?

Harmon County is in Zone 7b with an average last frost of March 31. Plan your Turnip planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Harmon County, OK?

Harmon County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is March 31 and first fall frost is November 5.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Harmon County gardeners in Zone 7b 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 Harmon County, OK. Local conditions may vary. Last updated: April 2026.