When to Plant Onion in San Augustine 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.
San Augustine County, Texas is in USDA Zone 8b. The average last spring frost is March 5 and the first fall frost is November 16, giving you a growing season of approximately 256 days.
At an elevation of 146 feet, San Augustine County receives approximately 62.7 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96°F, so Onion may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Onion will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Onion root diseases.
San Augustine County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.4-6.6
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
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Onion Planting Timeline — San Augustine County, TX
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 29 | Jan 29 – Feb 12 |
| Transplant Outdoors | March 5 | Mar 5 – Mar 19 |
| Direct Sow | February 19 | Feb 19 – Mar 12 |
| Fall Sowing | September 7 | Sep 7 – Sep 21 |
| Harvest | June 4 | Jun 4 – Jul 23 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | — |
| June | Harvest |
| July | Harvest |
| August | — |
| 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 8b
Growing Season
256 days
Growing Tips for San Augustine 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 San Augustine County, TX?
San Augustine County is in Zone 8b with an average last frost of March 5. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is San Augustine County, TX?
San Augustine County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 5 and first fall frost is November 16.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help San Augustine County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.
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