When to Plant Onion in Anderson County, TX
May in the garden — Anderson County, Texas
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Anderson County, Texas.
Before June arrives, get these ready
- 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.
Anderson County, Texas is in USDA Zone 8b. The average last spring frost is March 6 and the first fall frost is November 16, giving you a growing season of approximately 255 days.
At an elevation of 86 feet, Anderson County receives approximately 73.7 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.
Anderson County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.4-6.8
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.
Soil Compatibility in Anderson County
How your county's soil matches Onion's growing requirements.
Soil pH
Your soil pH (5.4–6.8) overlaps with Onion's range (6.0–7.0), though not a perfect match.
Soil Texture
Sandy soil in Anderson County warms quickly in spring but drains fast. Onion will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is low (1.9%). Add 2-3 inches of compost before planting Onion.
How to Plant Onion
Fall planting: Sow 10 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 | — | 2.9" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Apr | 4.3" | 7.9" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 11.5" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 11.3" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 8.8" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 10" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 6.1" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4.9" | 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 Anderson 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 — Anderson County, TX
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 30 | Jan 30 – Feb 13 |
| Transplant Outdoors | March 6 | Mar 6 – Mar 20 |
| Direct Sow | February 20 | Feb 20 – Mar 13 |
| Harvest | June 5 | Jun 5 – Jul 24 |
| Fall Sowing | September 7 | Sep 7 – Sep 21 |
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
1"/week · Natural rainfall sufficient
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
255 days in Anderson County
Growing Tips for Onion in Anderson County
Direct sow Onion outdoors after March 06 in Anderson County when soil has warmed and frost danger has passed.
Sandy soil in Anderson County dries quickly — mulch Onion with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
With summer highs reaching 96°F in Anderson County, provide afternoon shade for Onion and water deeply in the morning.
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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Onion in Other Locations
Frequently Asked Questions
When should I plant Onion in Anderson County, TX?
Anderson County is in Zone 8b 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 Anderson County, TX?
Anderson County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 6 and first fall frost is November 16.
Your Anderson County Garden Planner — Free
A 24-page printable planner built for Anderson County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.