When to Plant Onion in Gillespie 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.
Gillespie 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 3,036 feet, Gillespie County receives approximately 65.8 inches of rainfall annually with predominantly loam soil. Summer highs average 91°F, providing good warmth for Onion during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Onion root diseases.
Gillespie County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.8
Drainage
Well Drained
Plant Planting Risk Windows
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
Onion Planting Timeline — Gillespie County, TX
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 12 | Feb 12 – Feb 26 |
| Transplant Outdoors | March 19 | Mar 19 – Apr 2 |
| Direct Sow | March 5 | Mar 5 – Mar 26 |
| Fall Sowing | September 5 | Sep 5 – Sep 19 |
| Harvest | June 18 | Jun 18 – Aug 6 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Transplant Outdoors Direct Sow |
| April | Transplant Outdoors |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
90–120 days
Soil pH
6 – 7
USDA Zone
Zone 8a
Growing Season
240 days
Growing Tips for Gillespie 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
Level Up Your Garden
Onion in Other Locations
Frequently Asked Questions
When should I plant Onion in Gillespie County, TX?
Gillespie County is in Zone 8a with an average last frost of March 19. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Gillespie County, TX?
Gillespie County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 19 and first fall frost is November 14.
Plan Your Garden with Confidence
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