Frost Dates for Dover, DE
In Dover, DE, the average last spring frost is around Apr 4 and the average first fall frost around Nov 4, for a growing season of about 214 days. For frost-tender plants, wait until Apr 17, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the Dover, DE weather station, 1 mile away, elevation 30 ft. Frost can come earlier in low spots and valleys and later near cities and large lakes.
Frost probability by date
Chance of a 32°F frost after the spring date, or before the fall date.
| Chance | Last spring frost | First fall frost |
|---|---|---|
| 10% | Apr 17 | Oct 23 |
| 20% | Apr 12 | Oct 28 |
| 30% | Apr 9 | Oct 31 |
| 40% | Apr 6 | Nov 2 |
| 50% | Apr 4 | Nov 4 |
| 60% | Apr 1 | Nov 6 |
| 70% | Mar 31 | Nov 9 |
| 80% | Mar 28 | Nov 13 |
| 90% | Mar 22 | Nov 18 |
Light frost vs. hard freeze
Average (50%) dates for each temperature. Tender plants are damaged at 36°F; most hardy crops survive until 28°F.
| Temperature | Last in spring | First in fall |
|---|---|---|
| Light frost (36°F) | Apr 17 | Oct 25 |
| Frost / freeze (32°F) | Apr 4 | Nov 4 |
| Hard freeze (28°F) | Mar 25 | Nov 16 |
Planting calendar for Dover
Transplant Apr 11 – Apr 25
Transplant Apr 18 – May 2
Transplant Apr 18 – May 2
Transplant Apr 11 – Apr 25
Sow or transplant Apr 11 – Apr 25
Sow or transplant Apr 11 – Apr 25
Sow or transplant Apr 18 – May 2
Sow or transplant Mar 7 – Mar 21
Fall sowing Sep 9 – Oct 7
Fall sowing Sep 9 – Sep 30
Fall sowing Aug 26 – Sep 9
Sow or transplant Mar 7 – Mar 21
Fall sowing Aug 26 – Sep 23
Transplant Mar 21 – Apr 4
Fall sowing Aug 12 – Aug 26
Transplant Mar 14 – Mar 28
Fall sowing Aug 12 – Aug 26
Fall sowing Aug 12 – Aug 26
Fall sowing Sep 23 – Oct 14
Fall sowing Aug 26 – Sep 9
Plant Mar 7 – Mar 21
Based on the average last frost (Apr 4) and first frost (Nov 4). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.