When to Plant Onion in Obion County, TN
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.
Obion County, Tennessee is in USDA Zone 7a. The average last spring frost is April 2 and the first fall frost is October 28, giving you a growing season of approximately 209 days.
At an elevation of 1,431 feet, Obion County receives approximately 44.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Onion during the growing season.
Obion County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-7
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.
Plant Water Budget
Onion Planting Timeline — Obion County, TN
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 26 | Feb 26 – Mar 12 |
| Transplant Outdoors | April 2 | Apr 2 – Apr 16 |
| Direct Sow | March 19 | Mar 19 – Apr 9 |
| Fall Sowing | August 19 | Aug 19 – Sep 2 |
| Harvest | July 2 | Jul 2 – Aug 20 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | — |
| 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
6 – 7
USDA Zone
Zone 7a
Growing Season
209 days
Growing Tips for Obion 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
Level Up Your Garden
Onion in Other Locations
Frequently Asked Questions
When should I plant Onion in Obion County, TN?
Obion County is in Zone 7a with an average last frost of April 2. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Obion County, TN?
Obion County, Tennessee is in USDA Hardiness Zone 7a. The average last spring frost is April 2 and first fall frost is October 28.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Obion County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.
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