When to Plant Onion in Marion County, MS
May to-do list for Marion County, Mississippi
We've pulled the most time-sensitive tasks for Marion County, Mississippi this May and put them front and centre. Tackle them in order.
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.
Marion County, Mississippi is in USDA Zone 8b. The average last spring frost is March 8 and the first fall frost is November 20, giving you a growing season of approximately 257 days.
At an elevation of 330 feet, Marion County receives approximately 48.2 inches of rainfall annually with predominantly clay loam soil. Summer highs average 91°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.
Marion County Soil Profile
Soil Type
Clay Loam
Soil pH
5.3-6.3
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 | — | 3.7" | 0" | ❄️ Dormant |
| Feb | — | 3.5" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| May | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Jun | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5.7" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Sep | 4.3" | 4" | 0.3" | 💧 Light watering |
| Oct | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Nov | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Dec | — | 3.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Marion County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Onion Planting Timeline — Marion County, MS
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 1 | Feb 1 – Feb 15 |
| Transplant Outdoors | March 8 | Mar 8 – Mar 22 |
| Direct Sow | February 22 | Feb 22 – Mar 15 |
| Harvest | June 7 | Jun 7 – Jul 26 |
| Fall Sowing | September 11 | Sep 11 – Sep 25 |
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 | — |
| 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 8b
📆 Growing Season
257 days in Marion County
Growing Tips for Marion 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 Marion County, MS?
Marion County is in Zone 8b with an average last frost of March 8. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Marion County, MS?
Marion County, Mississippi is in USDA Hardiness Zone 8b. The average last spring frost is March 8 and first fall frost is November 20.
Your Marion County Garden Planner — Free
A 24-page printable planner built for Marion 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.