When to Plant Onion in Concho 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.
Concho County, Texas is in USDA Zone 8a. The average last spring frost is March 25 and the first fall frost is November 12, giving you a growing season of approximately 232 days.
At an elevation of 3,848 feet, Concho County receives approximately 58.2 inches of rainfall annually with predominantly loam soil. Summer highs average 93°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.
Concho County Soil Profile
Soil Type
Loam
Soil pH
6.6-7.4
Drainage
Well Drained
Monthly Watering Guide for Onion
Onion needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Onion Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 2.2" | 0" | ❄️ Dormant |
| Mar | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Apr | 4.3" | 6.8" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 8.9" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 9.3" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 6.8" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 6.5" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 5.4" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Nov | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Concho County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Onion Planting Timeline — Concho County, TX
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 18 | Feb 18 – Mar 4 |
| Transplant Outdoors | March 25 | Mar 25 – Apr 8 |
| Direct Sow | March 11 | Mar 11 – Apr 1 |
| Harvest | June 24 | Jun 24 – Aug 12 |
| Fall Sowing | September 3 | Sep 3 – Sep 17 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| 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
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 8a
📆 Growing Season
232 days in Concho County
Growing Tips for Concho 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
Check more plant combinations with our Companion Planting Checker →
Onion in Other Locations
Frequently Asked Questions
When should I plant Onion in Concho County, TX?
Concho County is in Zone 8a with an average last frost of March 25. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Concho County, TX?
Concho County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 25 and first fall frost is November 12.
Your Concho County Garden Planner — Free
A 22-page printable planner built for Concho County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.