Delaware frost dates

Average last spring and first fall frost dates for Delaware’s largest cities, with each city’s USDA hardiness zone.

Reviewed October 2026

Among Delaware’s 20 largest cities, the average last spring frost ranges from Mar 29 in Lewes to Apr 11 in Milford. Elevation, distance from the coast and city heat all shift the date, so use your own ZIP code below for the closest match.

City	Average last spring frost	Average first fall frost	Frost-free days	Hardiness zone	Weather station used
Wilmington	Apr 7	Nov 4	211	7b	Wilmington Porter RSch, DE, 3 mi
Dover	Apr 4	Nov 4	214	7b	Dover, DE
Newark	Apr 7	Nov 2	209	7a–7b	Newark Ag Farm, DE
Middletown	Apr 7	Nov 2	209	7b	Newark Ag Farm, DE, 16 mi
Milford	Apr 11	Oct 30	202	7b	Greenwood 2Ne, DE, 11 mi
Smyrna	Apr 4	Nov 4	214	7b	Dover, DE, 12 mi
Seaford	Apr 11	Oct 30	202	7b	Greenwood 2Ne, DE, 11 mi
Georgetown	Apr 4	Nov 6	216	7b	Georgetown Sussex Co Airport, DE, 2 mi
Millsboro	Apr 4	Nov 6	216	7b	Georgetown Sussex Co Airport, DE, 7 mi
Elsmere	Apr 7	Nov 4	211	7b	Wilmington Porter RSch, DE, 4 mi
New Castle	Apr 7	Nov 1	208	7b	Wilmington New Castle Co Airport, DE, 2 mi
Clayton	Apr 4	Nov 4	214	7b	Dover, DE, 11 mi
Laurel	Apr 2	Nov 10	222	7b	Salisbury 2N, MD, 11 mi
Camden	Apr 4	Nov 4	214	7b	Dover, DE, 4 mi
Harrington	Apr 11	Oct 30	202	7b	Greenwood 2Ne, DE, 7 mi
Milton	Apr 4	Nov 6	216	7b	Georgetown Sussex Co Airport, DE, 7 mi
Lewes	Mar 29	Nov 14	230	7b	Lewes, DE
Selbyville	Apr 7	Nov 2	209	7b	Ocean City Muni Airport, MD, 11 mi
Ocean View	Apr 7	Nov 2	209	7b–8a	Ocean City Muni Airport, MD, 15 mi
Townsend	Apr 7	Nov 2	209	7b	Newark Ag Farm, DE, 18 mi

Frost dates are the dates after (spring) or before (fall) which the chance of a 32°F freeze is below 50%, from NOAA’s 1991–2020 U.S. Climate Normals for the weather station nearest each city’s center. Zones are from the 2023 USDA Plant Hardiness Zone Map for the ZIP codes around each city; a range means nearby ZIP codes differ. Cities are the 20 largest by Census Bureau 2024 population estimates.

An average is not a guarantee. There’s still about a 1 in 2 chance of frost after the average last spring date. Many gardeners wait an extra week or two before setting out tomatoes, peppers and basil, and keep covers handy.

Planting dates for Wilmington

Timed from Wilmington’s average last frost of Apr 7, using University of New Hampshire Extension’s planting guidance. For your exact dates, enter your ZIP code in the calendar below.

Crop	Start seeds indoors	Plant outside
Tomatoes	Feb 17 to Mar 3	Apr 14 to Apr 21
Peppers	Feb 10 to Feb 24	Apr 21
Lettuce	Feb 3 to Feb 10	Mar 10 to Mar 17
Broccoli	Jan 27 to Feb 10	Mar 10 to Mar 24
Cucumbers	Mar 17 to Mar 24	Apr 14 to Apr 21
Basil	Feb 24 to Mar 10	Apr 21

When to plant, for your garden

Your seed-starting and planting dates, timed from your last spring frost. Full calendar, 12 crops.

ZIP code

Last frost date

Enter your ZIP code to look up your average last frost date and hardiness zone, or type the date in yourself.

Frost dates: NOAA U.S. Climate Normals, 1991–2020. Hardiness zones: USDA Plant Hardiness Zone Map, 2023, ZIP code data from PRISM Group, Oregon State University, prism.oregonstate.edu, accessed Oct. 20, 2026.

More about frost dates

How to find your last frost date, and what your zone means · Full planting calendar · How to start seeds indoors

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