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When to Plant Onion in Comanche County, TX

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.

Comanche County, Texas is in USDA Zone 8a. The average last spring frost is March 19 and the first fall frost is November 14, giving you a growing season of approximately 240 days.

At an elevation of 2,216 feet, Comanche County receives approximately 59.6 inches of rainfall annually with predominantly loam soil. Summer highs average 91ยฐF, providing good warmth for Onion during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Onion root diseases.

Comanche County, TX (Zone 8a) Long season
240 days
Last Spring Frost March 19
240 growing days
First Fall Frost November 14

Comanche County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (101 days to spare)
Start indoors: Feb 1 Transplant: Mar 8 🍅 Harvest: Jun 7 – Jul 26
Recommended (50%) ✓ Fits season (100 days to spare)
Start indoors: Feb 12 Transplant: Mar 19 🍅 Harvest: Jun 18 – Aug 6
Safe Start (90%) ✓ Fits season (95 days to spare)
Start indoors: Mar 8 Transplant: Apr 12 🍅 Harvest: Jul 12 – Aug 30

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
1.0″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 549 gal / 100 sq ft
Onion needs ~1,916 GDD — county provides 4,380 GDD Excellent fit

Onion Planting Timeline โ€” Comanche County, TX

Onion Planting Calendar

Activity When Date Range
Start Indoors February 12 Feb 12 โ€“ Feb 26
Transplant Outdoors March 19 Mar 19 โ€“ Apr 2
Direct Sow March 5 Mar 5 โ€“ Mar 26
Fall Sowing September 5 Sep 5 โ€“ Sep 19
Harvest June 18 Jun 18 โ€“ Aug 6

Plant 1" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

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

90โ€“120 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 8a

Growing Season

240 days

Growing Tips for Comanche 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 Comanche County, TX?

Comanche County is in Zone 8a with an average last frost of March 19. Plan your Onion planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Comanche County, TX?

Comanche County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 19 and first fall frost is November 14.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Comanche County gardeners in Zone 8a 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 Comanche County, TX. Local conditions may vary. Last updated: April 2026.