Root Vegetable

When to Plant Onions in Louisiana

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

The Short Answer

In Louisiana, soil conditions are an important factor for onions. Rich alluvial soils in river valleys. Heavy clay in many areas. Acidic throughout. Sandy in some coastal areas. Direct sow 4 weeks before your last frost date.

Louisiana Frost Dates

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

Region Zones Last Frost (Spring) First Frost (Fall)
Northern Louisiana 8a, 8b Mar 1 - Mar 15 Nov 10 - Nov 25
Southern Louisiana 9a, 9b Feb 1 - Feb 20 Dec 1 - Dec 20

Onions Planting Schedule for Louisiana

Northern Louisiana (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 Louisiana (Zones 9a, 9b)

Average last frost: Feb 1 - Feb 20 · Average first frost: Dec 1 - Dec 20

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

Growing Onions in Louisiana

Onions in Louisiana'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 Louisiana

Rich alluvial soils in river valleys. Heavy clay in many areas. Acidic throughout. Sandy in some coastal areas. Loose, well-drained soil is especially important for onions since the edible portion grows underground. If your soil is heavy clay, consider raised beds.

Louisiana Climate & Growing Season

Subtropical. Long growing season. Very hot and humid summers — some crops need shade. Year-round gardening possible. Onions can handle frost well, which is an advantage in Louisiana's climate. You can push planting dates earlier in spring and extend into fall.

Growing season length varies across Louisiana: Northern Louisiana (8a, 8b) has a last frost around Mar 1 - Mar 15, while Southern Louisiana (9a, 9b) sees frost end around Feb 1 - Feb 20. 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 Louisiana, but your exact planting dates depend on which region you're in. Northern Louisiana gardeners should plan around a Mar 1 - Mar 15 last frost, while those in Southern Louisiana can typically plant earlier. For exact dates based on your zip code, use our free planting date finder.

Related Guides

Onions Growing Guide National planting guide with all states Louisiana Planting Calendar All plants for Louisiana Onions in Alabama Alabama planting dates Onions in Alaska Alaska planting dates Onions in Arizona Arizona planting dates Onions in Arkansas Arkansas planting dates
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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