Root Vegetable

When to Plant Onions in Mississippi

The backbone of the kitchen garden. Choose short-day, intermediate, or long-day varieties based on your latitude.

The Short Answer

In Mississippi, soil conditions are an important factor for onions. Rich delta soils in west. Heavy clay in many areas. Sandy in pine belt. Acidic throughout. Direct sow 4 weeks before your last frost date.

Mississippi Frost Dates

Your planting dates depend on which part of Mississippi you're in. Here are the frost date ranges by region:

Region Zones Last Frost (Spring) First Frost (Fall)
Northern Mississippi 7b, 8a Mar 15 - Apr 1 Nov 1 - Nov 15
Central Mississippi 8a, 8b Mar 1 - Mar 15 Nov 10 - Nov 25
Southern Mississippi 8b, 9a Feb 15 - Mar 5 Nov 15 - Dec 5

Onions Planting Schedule for Mississippi

Northern Mississippi (Zones 7b, 8a)

Average last frost: Mar 15 - Apr 1 · Average first frost: Nov 1 - Nov 15

Start Seeds Indoors
10 wks before frost
Transplant Outside
4 wks before frost
Direct Sow
4 wks before frost

Central Mississippi (Zones 8a, 8b)

Average last frost: Mar 1 - Mar 15 · Average first frost: Nov 10 - Nov 25

Start Seeds Indoors
10 wks before frost
Transplant Outside
4 wks before frost
Direct Sow
4 wks before frost

Southern Mississippi (Zones 8b, 9a)

Average last frost: Feb 15 - Mar 5 · Average first frost: Nov 15 - Dec 5

Start Seeds Indoors
10 wks before frost
Transplant Outside
4 wks before frost
Direct Sow
4 wks before frost

Growing Onions in Mississippi

Onions in Mississippi's Climate

You straddle the day-length divide. Southern areas need short-day varieties (plant in fall for spring harvest), northern areas can use intermediate-day types. The single most important decision for onion success in your zone is choosing the right day-length type — the wrong one produces scallions instead of bulbs regardless of how well you grow them.

Soil Considerations for Mississippi

Rich delta soils in west. Heavy clay in many areas. Sandy in pine belt. Acidic throughout. Loose, well-drained soil is especially important for onions since the edible portion grows underground. If your soil is heavy clay, consider raised beds.

Mississippi Climate & Growing Season

Long growing season. Hot, humid summers. Mild winters. Two-season gardening possible. Onions can handle frost well, which is an advantage in Mississippi's climate. You can push planting dates earlier in spring and extend into fall.

Growing season length varies across Mississippi: Northern Mississippi (7b, 8a) has a last frost around Mar 15 - Apr 1, while Southern Mississippi (8b, 9a) sees frost end around Feb 15 - Mar 5. This difference matters for onions — but onions handle frost well, so the timing difference is less critical.

Growing Tips

Day length triggers bulbing. Northern gardeners need long-day varieties. Southern gardeners need short-day varieties.

Companion Planting

Plant onions alongside these companions for better growth:

Carrots Lettuce Beets Tomatoes

Keep onions away from:

Beans Peas

The Bottom Line

Onions can be grown successfully across Mississippi, but your exact planting dates depend on which region you're in. Northern Mississippi gardeners should plan around a Mar 15 - Apr 1 last frost, while those in Southern Mississippi can typically plant earlier. For exact dates based on your zip code, use our free planting date finder.
Note: All dates are based on NOAA 30-year Climate Normals and represent historical averages, not predictions for any specific year. Always check your local weather forecast before planting frost-sensitive crops. Learn about our data sources.

Last reviewed: March 29, 2026

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