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USDA Hardiness Zone 7b

Frost Dates for 19968 — Milton, Delaware

NOAA 1991–2020 normals from Georgetown Sussex Co Airport, DE (51 ft), 7 miles southwest.

Updated

In Milton, the last spring frost (32°F) is around April 4 in half of years and has passed by April 16 in nine years out of ten. The first fall frost comes around November 6, as early as October 23 one year in ten, leaving a typical freeze-free season of 217 days (NOAA, Georgetown Sussex Co Airport, DE).

Last spring frost
April 4

50% probability

First fall frost
November 6

50% probability

Growing season
217 days

freeze-free, 50%

Hardiness zone
7b

5 to 10°F (-15.0 to -12.2°C) coldest night

First snow
December 28

median, 1991–2020

Last snow
March 1

median, 1991–2020

Winters with snow
100%

20 of 20 observed

Snow per year
12.8"

NOAA normal

Frost risk by date in Milton

Half of springs at Georgetown Sussex Co Airport, DE see their last 32°F night by April 4; only one in ten is past it by March 22, and one in ten still has one after April 16. Planting tender crops after April 9 leaves a 30% risk of a frost on them, after April 13 20%, and after April 16 10%. The 12 days between the even-odds date and the one-in-ten date is narrower than at 80% of the 10 Delaware stations behind this site's ZIP pages.

In fall the first 32°F night comes by November 6 in half of years, as early as October 23 one year in ten, and holds off past November 22 one year in ten. A hard freeze of 28°F follows 13 days later, around November 19; in spring the one-in-ten date for 28°F is April 5, 11 days before the 32°F one. The freeze-free season lasts 217 days in a typical year, longer than at 70% of the 10 Delaware stations; it reaches 239 days one year in ten and falls short of 198 one year in ten. On average 83 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 12 days longer, to about April 16, and return around October 27. Severe cold of 16°F or below comes in 94% of winters, usually between January 5 and February 8.

Spring: the chance of another night this cold after the date
Low90%80%70%60%50%40%30%20%10%
36°FApr 1Apr 6Apr 10Apr 14Apr 16Apr 19Apr 22Apr 26May 2
32°FMar 22Mar 27Mar 31Apr 1Apr 4Apr 6Apr 9Apr 13Apr 16
28°FMar 3Mar 11Mar 16Mar 20Mar 23Mar 26Mar 29Apr 1Apr 5
24°FFeb 20Feb 27Mar 2Mar 6Mar 10Mar 13Mar 17Mar 20Mar 25
20°FFeb 2Feb 9Feb 15Feb 20Feb 25Mar 1Mar 4Mar 8Mar 15
16°F94% of yrsJan 15Jan 27Jan 31Feb 3Feb 8Feb 13Feb 20Feb 27Mar 4
Fall: the chance the first night this cold has come by the date
Low10%20%30%40%50%60%70%80%90%
36°FOct 13Oct 18Oct 21Oct 24Oct 27Oct 29Nov 1Nov 3Nov 8
32°FOct 23Oct 28Oct 31Nov 2Nov 6Nov 9Nov 13Nov 16Nov 22
28°FNov 4Nov 8Nov 12Nov 15Nov 19Nov 23Nov 27Dec 1Dec 6
24°FNov 14Nov 21Nov 27Dec 1Dec 4Dec 7Dec 13Dec 19Dec 27
20°FDec 1Dec 6Dec 11Dec 16Dec 21Dec 27Jan 1Jan 5Jan 15
16°F94% of yrsDec 13Dec 22Dec 28Jan 1Jan 5Jan 10Jan 15Jan 23Jan 31

Freeze probabilities 1991–2020 at Georgetown Sussex Co Airport, DE, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.

Frost risk on any date in 19968 →Compare Milton with another place →

Weather by month in Milton

July is the warmest month at Georgetown Sussex Co Airport, DE, averaging 88°F by day and 70°F at night; January is the coldest at 45°F and 29°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 65% of years.

Warmth for growing adds up to 4,225 growing degree days a year (base 50°F), more than at 80% of the 10 Delaware stations. 35% of them (1,473) have built up by the end of June, and July adds the most, 886. Precipitation totals 43.9 inches a year, most in September (4.5") and least in February (2.6"); May to September bring 46% of it.

Monthly normals 1991–2020 at Georgetown Sussex Co Airport, DE
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan45293.0100%2216
Feb48302.6100%2020
Mar55363.999%1367
Apr66453.365%2213
May75553.60%0451
Jun83644.10%0706
Jul88704.10%0886
Aug86684.00%0828
Sep80614.50%0611
Oct69494.130%1303
Nov59403.295%890
Dec50333.5100%1934

Monthly normals 1991–2020 at Georgetown Sussex Co Airport, DE (51 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.

Compared with the next station

The nearest other station, Lewes, DE, 7 miles east of Milton, has a last frost 6 days earlier (March 29), a first frost 8 days later (November 14), a season 14 days longer.

Frost dates for 19958 (Lewes) →

When it snows in Milton, Delaware

The first measurable snow (0.1 inch or more) in Milton usually arrives around December 28, and the last of the season around March 1. Those are the middle dates across the winters of 1991–2020 at Greenwood 2NE, DE, 15.9 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 34 days after the last snow.

Planting calendar for 19968

What to do and when, from the 50% frost dates for Milton, Delaware
WhenWhat to do
January 24 – February 7Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
February 7 – February 21Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
March 7 – March 21Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 4 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by August 14Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by October 23Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
November 6 onwardPlant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter.

The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.

Where these figures come from

ZIP 19968 is 7 miles from Georgetown Sussex Co Airport, DE, which stands at 51 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 3 other ZIP codes share the station; its figures are presented in full for 19966 (Millsboro). The 2023 USDA Plant Hardiness Zone Map lists ZIP 19968 in zone 7b, the band where the coldest night of the year averaged 5 to 10°F (-15.0 to -12.2°C) over 1991–2020; a zone describes winter lows, not frost dates.

Frost dates across Delaware →

Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.

Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.

ZIP codes measured at the same station

Other zone 7b places in Delaware