When to Plant Onion in Tyler County, TX
Your May gardening checklist
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
June prep starts now
- First harvests: onion
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.
Tyler County, Texas is in USDA Zone 9a. The average last spring frost is March 6 and the first fall frost is November 19, giving you a growing season of approximately 258 days.
At an elevation of 378 feet, Tyler County receives approximately 75.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 95°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.
Tyler County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.4-6.3
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.
Soil Compatibility in Tyler County
How your county's soil matches Onion's growing requirements.
Soil pH
Your soil pH (5.4–6.3) is more acidic than Onion prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in Tyler County warms quickly in spring but drains fast. Onion will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Onion.
Organic Matter
Organic matter is moderate (2.1%). Annual compost additions will help Onion.
How to Plant Onion
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Plant Water Budget
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 | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 2.7" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 7.1" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 11.7" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 13.2" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 9.7" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 8.6" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 7.2" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 2.4" | 1.9" | 💧 Light watering |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Tyler County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Onion Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Onion Planting Timeline — Tyler County, TX
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 6 | Feb 6 – Feb 20 |
| Transplant Outdoors | March 6 | Mar 6 – Mar 20 |
| Direct Sow | February 13 | Feb 13 – Mar 6 |
| Harvest | June 5 | Jun 5 – Jul 24 |
| Fall Sowing | September 24 | Sep 24 – Oct 8 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | — |
| June | Harvest |
| July | Harvest |
| August | — |
| September | Fall Sowing |
| October | Fall Sowing |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 9a
📆 Growing Season
258 days in Tyler County
Growing Tips for Onion in Tyler County
Direct sow Onion outdoors after March 06 in Tyler County when soil has warmed and frost danger has passed.
Sandy soil in Tyler County dries quickly — mulch Onion with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Common pests for Onion in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.
General growing tips
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
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Check more plant combinations with our Companion Planting Checker →
Onion in Other Locations
Frequently Asked Questions
When should I plant Onion in Tyler County, TX?
Tyler County is in Zone 9a with an average last frost of March 6. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Tyler County, TX?
Tyler County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 6 and first fall frost is November 19.
Your Tyler County Garden Planner — Free
A 24-page printable planner built for Tyler County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.