When to plant Onion in Henry County, GA
In Henry County, plant Onion in spring between March 11 and April 1, once soil temps hold above 50°F. Henry County's last frost averages March 25, so most warm-season crops establish quickly once soil holds above 60°F. For a fall crop, sow between August 30 and September 13 — roughly 90–120 days before the first frost on November 8.
When to Plant Onion in Henry County, GA
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.
Henry County, Georgia is in USDA Zone 8a. The average last spring frost is March 25 and the first fall frost is November 8, giving you a growing season of approximately 228 days.
At an elevation of 379 feet, Henry County receives approximately 52.8 inches of rainfall annually with predominantly clay loam soil. Summer highs average 93°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.
Henry County Soil Profile
Soil Type
Clay Loam
Soil pH
5.6-6.7
Drainage
Well Drained
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 | — | 4.7" | 0" | ❄️ Dormant |
| Feb | — | 4.1" | 0" | ❄️ Dormant |
| Mar | 4.3" | 5.4" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| May | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Jun | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Jul | 4.3" | 5.5" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Nov | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Dec | — | 4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Henry County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Onion Planting Timeline — Henry County, GA
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 18 | Feb 18 – Mar 4 |
| Transplant Outdoors | March 25 | Mar 25 – Apr 8 |
| Direct Sow | March 11 | Mar 11 – Apr 1 |
| Harvest | June 24 | Jun 24 – Aug 12 |
| Fall Sowing | August 30 | Aug 30 – Sep 13 |
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 | Fall Sowing Harvest |
| 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
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 8a
📆 Growing Season
228 days in Henry County
Growing Tips for Henry 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
Check more plant combinations with our Companion Planting Checker →
Onion in Other Locations
Frequently Asked Questions
When should I plant Onion in Henry County, GA?
Henry County is in Zone 8a with an average last frost of March 25. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Henry County, GA?
Henry County, Georgia is in USDA Hardiness Zone 8a. The average last spring frost is March 25 and first fall frost is November 8.
When should I plant Onion in Henry County, GA?
In Henry County, GA, plant Onion after the last frost (around March 25) and before the first frost (around November 8). Best results when soil holds above 50°F.
What growing zone is Henry County, GA for Onion?
Henry County sits in USDA Zone 8a. Onion grows reliably in zones 3a through 10b, so it's a good fit here.
Can Onion grow in Henry County's climate?
Yes — Onion grows well in Henry County's temperate climate. Henry County averages a 228-day frost-free season, with last frost around March 25 and first frost around November 8.
Your Henry County Garden Planner — Free
A 22-page printable planner built for Henry County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.