Cool-Season Vegetable

When to Plant Cauliflower in Delaware

The diva of the brassica family. More temperamental than broccoli but worth the extra attention.

The Short Answer

Cauliflower are cold-tolerant and do well in Delaware's varied climate. Delaware gardeners can also plant a fall crop. 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

Cauliflower 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 before frost

Fall Planting

10 wks before first 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 before frost

Fall Planting

10 wks before first frost

Growing Cauliflower in Delaware

Cauliflower in Delaware's Climate

Fall cauliflower is more reliable than spring in your climate. The consistent cooling trend from September through October gives cauliflower the steady conditions it demands. Spring plantings risk bolting if temperatures spike above 80°F during heading. Start with fall production before attempting spring.

Soil Considerations for Delaware

Sandy soils in south, clay loam in north. Generally well-drained. Slightly acidic.

Delaware Climate & Growing Season

Moderate climate with maritime influence. Good growing conditions for a wide range of vegetables.

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 cauliflower — adjust your planting dates to match your specific region.

Growing Tips

Blanch white varieties by tying outer leaves over the head when it reaches 2 inches. Temperature swings cause buttoning.

Companion Planting

Plant cauliflower alongside these companions for better growth:

Beets Celery Onions

Keep cauliflower away from:

Strawberries Tomatoes

The Bottom Line

Cauliflower 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