When to Plant Onion in Covington County, AL
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.
Covington County, Alabama is in USDA Zone 8a. The average last spring frost is March 20 and the first fall frost is November 11, giving you a growing season of approximately 236 days.
At an elevation of 392 feet, Covington County receives approximately 50.6 inches of rainfall annually with predominantly clay loam soil. Summer highs average 95°F, so Onion may need afternoon shade and extra watering during peak heat. Clay soil retains moisture well for Onion, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Onion root diseases.
Covington County Soil Profile
Soil Type
Clay Loam
Soil pH
5.3-6.6
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.
Soil Compatibility in Covington County
How your county's soil matches Onion's growing requirements.
Soil pH
Your soil pH (5.3–6.6) is more acidic than Onion prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The clay loam soil in Covington County is excellent for Onion — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.5%). Annual compost additions will help 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 | — | 3.9" | 0" | ❄️ Dormant |
| Feb | — | 4.5" | 0" | ❄️ Dormant |
| Mar | 4.3" | 5.2" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| May | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Oct | 4.3" | 3" | 1.3" | 💧 Light watering |
| Nov | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Dec | — | 3.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Covington 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 — Covington County, AL
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 13 | Feb 13 – Feb 27 |
| Transplant Outdoors | March 20 | Mar 20 – Apr 3 |
| Direct Sow | March 6 | Mar 6 – Mar 27 |
| Harvest | June 19 | Jun 19 – Aug 7 |
| Fall Sowing | September 2 | Sep 2 – Sep 16 |
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
1"/week · Only during dry spells
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 8a
📆 Growing Season
236 days in Covington County
Growing Tips for Onion in Covington County
Direct sow Onion outdoors after March 20 in Covington County when soil has warmed and frost danger has passed.
With Covington County's clay soil (33% clay), work in 3-4 inches of compost before planting Onion. Avoid tilling when soil is wet to prevent compaction.
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 Covington County, AL?
Covington County is in Zone 8a with an average last frost of March 20. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Covington County, AL?
Covington County, Alabama is in USDA Hardiness Zone 8a. The average last spring frost is March 20 and first fall frost is November 11.
Plan Your Garden with Confidence
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