When to Plant Basil in Delaware
The king of herbs. Basil and tomatoes are best friends in the garden and in the kitchen.
The Short Answer
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 |
Basil Planting Schedule for Delaware
Northern Delaware (Zones 7a)
Average last frost: Apr 10 - Apr 25 · Average first frost: Oct 10 - Oct 25
Southern Delaware (Zones 7b)
Average last frost: Apr 1 - Apr 15 · Average first frost: Oct 20 - Nov 5
Growing Basil in Delaware
Basil in Delaware's Climate
Your summer warmth grows excellent basil from transplant through first frost. Start indoors 6 weeks before last frost or buy transplants. Basil peaks in July-August when heat intensifies the essential oils. Succession plant or pinch flowers to keep production going. Plant near tomatoes — the classic companion pairing that works in the kitchen as well as the garden.
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 basil outside.
Delaware Climate & Growing Season
Moderate climate with maritime influence. Good growing conditions for a wide range of vegetables. Basil 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 basil — transplant timing shifts by several weeks across the state.
Growing Tips
Pinch off flower buds to keep leaves producing. Harvest from the top down, cutting just above a leaf pair. Succession plant for season-long supply.
Companion Planting
Plant basil alongside these companions for better growth:
Keep basil away from:
The Bottom Line
Last reviewed: March 29, 2026