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When to Plant Onion in Perry County, TN

Onions are a fundamental kitchen staple available in yellow, white, and red varieties. Choose long-day, short-day, or intermediate types based on your latitude.

Perry County, Tennessee is in USDA Zone 7a. The average last spring frost is April 9 and the first fall frost is October 26, giving you a growing season of approximately 200 days.

At an elevation of 2,303 feet, Perry County receives approximately 54.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92ยฐF, providing good warmth for Onion during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Onion root diseases.

Perry County, TN (Zone 7a) Long season
200 days
Last Spring Frost April 9
200 growing days
First Fall Frost October 26

Perry County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (62 days to spare)
Start indoors: Feb 24 Transplant: Mar 31 🍅 Harvest: Jun 30 – Aug 18
Recommended (50%) ✓ Fits season (60 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: Jul 9 – Aug 27
Safe Start (90%) ✓ Fits season (65 days to spare)
Start indoors: Mar 17 Transplant: Apr 21 🍅 Harvest: Jul 21 – Sep 8

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
Onion needs ~1,995 GDD — county provides 3,800 GDD Excellent fit

Onion Planting Timeline โ€” Perry County, TN

Onion Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 โ€“ Mar 19
Transplant Outdoors April 9 Apr 9 โ€“ Apr 23
Direct Sow March 26 Mar 26 โ€“ Apr 16
Fall Sowing August 17 Aug 17 โ€“ Aug 31
Harvest July 9 Jul 9 โ€“ Aug 27

Plant 1" deep ยท 6" 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 โ€”
June โ€”
July Harvest
August Fall Sowing Harvest
September โ€”
October โ€”
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

6 โ€“ 7

USDA Zone

Zone 7a

Growing Season

200 days

Growing Tips for Perry County

Start seeds indoors 8-10 weeks before transplanting. Match day-length type to your latitude. Stop watering when tops begin to fall over and cure bulbs for 2-3 weeks before storage.

Companion Planting

Good Companions

Avoid Planting Near

  • Peas
  • Green Beans
  • Asparagus

Level Up Your Garden

Frequently Asked Questions

When should I plant Onion in Perry County, TN?

Perry County is in Zone 7a with an average last frost of April 9. Plan your Onion planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Perry County, TN?

Perry County, Tennessee is in USDA Hardiness Zone 7a. The average last spring frost is April 9 and first fall frost is October 26.

๐ŸŒฑ

Plan Your Garden with Confidence

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