When to plant Onion in Clarke County, GA
Aim to plant Onion in Clarke County on or after March 12; the window stays open through April 2. Clarke County's 229-day frost-free season gives you enough for a full main crop and a short fall succession. A second sowing from September 1 to September 15 extends the harvest into fall.
When to Plant Onion in Clarke County, GA
What to do in July
If you only do a handful of things in the garden this July, make it these. They're sequenced around your zone's frost timing.
-
Basket week: onion
Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.
Looking ahead to August
- 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.
Clarke County, Georgia is in USDA Zone 8b. The average last spring frost is March 26 and the first fall frost is November 10, giving you a growing season of approximately 229 days.
At an elevation of 286 feet, Clarke County receives approximately 60.1 inches of rainfall annually with predominantly clay loam soil. Summer highs average 94°F, providing good warmth for Onion during the growing season. 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.
Clarke County Soil Profile
Soil Type
Clay Loam
Soil pH
5.3-6.5
Drainage
Well Drained
Onion 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 Clarke County
How your county's soil matches Onion's growing requirements.
Soil pH
Your soil pH (5.3–6.5) is more acidic than Onion prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The clay loam soil in Clarke County is excellent for Onion — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help Onion.
How to Plant Onion
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Onion Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 4.4" | 0" | ❄️ Dormant |
| Feb | — | 4.5" | 0" | ❄️ Dormant |
| Mar | 4.3" | 5.7" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5.9" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 6.9" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 6.3" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Oct | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Nov | 4.3" | 4.9" | 0" | ✅ Rainfall sufficient |
| Dec | — | 5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Clarke 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 — Clarke County, GA
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 19 | Feb 19 – Mar 5 |
| Transplant Outdoors | March 26 | Mar 26 – Apr 9 |
| Direct Sow | March 12 | Mar 12 – Apr 2 |
| Harvest | June 25 | Jun 25 – Aug 13 |
| Fall Sowing | September 1 | Sep 1 – Sep 15 |
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
1"/week · Natural rainfall sufficient
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 8b
📆 Growing Season
229 days in Clarke County
Growing Tips for Onion in Clarke County
Direct sow Onion outdoors after March 26 in Clarke County when soil has warmed and frost danger has passed.
With Clarke County's clay soil (29% 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
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 Clarke County, GA?
Clarke County is in Zone 8b with an average last frost of March 26. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clarke County, GA?
Clarke County, Georgia is in USDA Hardiness Zone 8b. The average last spring frost is March 26 and first fall frost is November 10.
When should I plant Onion in Clarke County, GA?
In Clarke County, GA, plant Onion after the last frost (around March 26) and before the first frost (around November 10). Best results when soil holds above 50°F.
What growing zone is Clarke County, GA for Onion?
Clarke County sits in USDA Zone 8b. Onion grows reliably in zones 3a through 10b, so it's a good fit here.
Can Onion grow in Clarke County's climate?
Yes — Onion grows well in Clarke County's temperate climate. Clarke County averages a 229-day frost-free season, with last frost around March 26 and first frost around November 10.
Your Clarke County Garden Planner — Free
A 22-page printable planner built for Clarke 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.