Warm-Season Vegetable

When to Plant Tomatoes in Delaware

America's favorite garden vegetable (technically a fruit). Nothing beats a sun-warmed tomato straight off the vine.

The Short Answer

In Delaware, tomatoes planting dates vary by region. In Northern Delaware, your average last frost is around Apr 10 - Apr 25, while Southern Delaware sees its last frost around Apr 1 - Apr 15. Since tomatoes are frost-sensitive, start seeds indoors 6 weeks before your last frost, then transplant outside 2 weeks after frost danger has passed. Sandy soils in south, clay loam in north. Generally well-drained. Slightly acidic.

Delaware Frost Dates

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

Region Zones Last Frost (Spring) First Frost (Fall)
Northern Delaware 7a Apr 10 - Apr 25 Oct 10 - Oct 25
Southern Delaware 7b Apr 1 - Apr 15 Oct 20 - Nov 5

Tomatoes Planting Schedule for Delaware

Northern Delaware (Zones 7a)

Average last frost: Apr 10 - Apr 25 · Average first frost: Oct 10 - Oct 25

Start Seeds Indoors
6 wks before frost
Transplant Outside
2 wks after frost
Direct Sow
2 wks after frost

Southern Delaware (Zones 7b)

Average last frost: Apr 1 - Apr 15 · Average first frost: Oct 20 - Nov 5

Start Seeds Indoors
6 wks before frost
Transplant Outside
2 wks after frost
Direct Sow
2 wks after frost

Growing Tomatoes in Delaware

Tomatoes in Delaware's Climate

Your moderate climate with 170-200 frost-free days is solid tomato territory. Most standard varieties have plenty of time to produce, and you don't need the extreme heat management that southern growers face. Start seeds indoors 6 weeks before your last frost date and transplant once nights stay above 55°F. Ohio, Pennsylvania, and Indiana gardeners have been growing excellent tomatoes for generations — the climate is right in the sweet spot.

Soil Considerations for Delaware

Sandy soils in south, clay loam in north. Generally well-drained. Slightly acidic. Make sure soil has warmed to at least 60°F before planting tomatoes outside.

Delaware Climate & Growing Season

Moderate climate with maritime influence. Good growing conditions for a wide range of vegetables. Tomatoes cannot tolerate any frost, so wait until all frost danger has passed before transplanting outside. Watch local forecasts carefully in spring.

Growing season length varies across Delaware: Northern Delaware (7a) has a last frost around Apr 10 - Apr 25, while Southern Delaware (7b) sees frost end around Apr 1 - Apr 15. This difference matters for tomatoes — transplant timing shifts by several weeks across the state.

Growing Tips

Pinch off suckers for indeterminate varieties. Stake or cage for best results. Water at the base, not overhead, to prevent blight.

Companion Planting

Plant tomatoes alongside these companions for better growth:

Basil Carrots Peppers Marigolds

Keep tomatoes away from:

Brassicas Fennel Dill

The Bottom Line

Tomatoes can be grown successfully across Delaware, but your exact planting dates depend on which region you're in. Northern Delaware gardeners should plan around a Apr 10 - Apr 25 last frost, while those in Southern Delaware 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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