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When to Plant Sweet Potatoes in Guernsey County, OH

Sweet potatoes are a warm-season root crop that produces nutritious, sweet tubers in orange, white, and purple varieties. They need a long, hot growing season.

Guernsey County, Ohio is in USDA Zone 6a. The average last spring frost is April 30 and the first fall frost is October 16, giving you a growing season of approximately 169 days.

At an elevation of 790 feet, Guernsey County receives approximately 30.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91ยฐF, providing good warmth for Sweet Potatoes during the growing season.

Guernsey County, OH (Zone 6a) Moderate season
169 days
Last Spring Frost April 30
169 growing days
First Fall Frost October 16

Guernsey County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (11 days to spare)
Start indoors: Mar 2 Transplant: May 11 🍅 Harvest: Aug 10 – Sep 28
Recommended (50%) ✓ Fits season (15 days to spare)
Start indoors: Mar 5 Transplant: May 14 🍅 Harvest: Aug 13 – Oct 1
Safe Start (90%) ✓ Fits season (9 days to spare)
Start indoors: Mar 22 Transplant: May 31 🍅 Harvest: Aug 30 – Oct 18

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
0.8″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 375 gal / 100 sq ft
Sweet Potatoes needs ~1,916 GDD — county provides 3,084 GDD Excellent fit

Sweet Potatoes Planting Timeline โ€” Guernsey County, OH

Sweet Potatoes Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 โ€“ Mar 19
Transplant Outdoors May 14 May 14 โ€“ May 28
Direct Sow May 7 May 7 โ€“ May 28
Harvest August 13 Aug 13 โ€“ Oct 1

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

90โ€“120 days

Soil pH

5.5 โ€“ 6.5

USDA Zone

Zone 6a

Growing Season

169 days

Growing Tips for Guernsey County

Plant slips (rooted sprouts) after soil is thoroughly warm. Build raised mounds for better root development. Cure harvested roots at 80-85F for 10 days to develop sweetness.

Companion Planting

Good Companions

Avoid Planting Near

  • Squash Summer

Level Up Your Garden

Frequently Asked Questions

When should I plant Sweet Potatoes in Guernsey County, OH?

Guernsey County is in Zone 6a with an average last frost of April 30. Plan your Sweet Potatoes planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Guernsey County, OH?

Guernsey County, Ohio is in USDA Hardiness Zone 6a. The average last spring frost is April 30 and first fall frost is October 16.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Guernsey County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.

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Free download. Plan your entire garden season in minutes.

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