When to plant in Wilmington, DE
USDA Zone 7bEverything below — frost dates, hardiness zone, and what to plant when in Wilmington, Delaware — is derived from the closest NOAA station with complete climate normals.
In zone 7b, Wilmington supports a wide range of perennials year-round; the frost dates above are what set your annual vegetable timing.
Frost probability
WILMINGTON PORTER RSCH · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Wilmington’s own odds, recorded at WILMINGTON PORTER RSCH.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 7 | Apr 20 | Apr 6 | Oct 9 | Oct 24 | Nov 6 |
| 32°F | Apr 24 | Apr 7 | Mar 26 | Oct 21 | Nov 4 | Nov 19 |
| 28°F | Apr 10 | Mar 29 | Mar 13 | Nov 1 | Nov 15 | Dec 2 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Wilmington, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 13 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Wilmington planting FAQ
When is the last spring frost in Wilmington, DE?
Wilmington's average last spring frost falls near April 7 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.
When is the first fall frost in Wilmington, DE?
In Wilmington, the first 32°F freeze of fall lands around November 4 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Wilmington in?
Wilmington is in USDA hardiness zone 7b. In zone 7b, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Wilmington?
Wilmington has about 211 frost-free days — a long growing season — between the average last spring frost (April 7) and first fall frost (November 4).
When should I plant tomatoes in Wilmington?
For Wilmington, sow tomatoes indoors about February 10–February 24 and move the seedlings out around April 14, after the last spring frost.
Never miss a window in Wilmington
An email when it’s time to start seeds, transplant, and sow — timed to Wilmington’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Pennsville · 10 km
- Hockessin · 14 km
- Pike Creek Valley · 14 km
- Brookside · 17 km
- Bear · 18 km
- Chester · 18 km
- Newark · 20 km
- Glasgow · 24 km
Frost dates recorded at WILMINGTON PORTER RSCH, 4 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Wilmington, DE — Frost Dates & Zone 7b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00079605. Retrieved from https://blissgarden.com/delaware/wilmington.