Soilclock

Wilmington 54°F soil temperature

4 inches down: 56°F · 7-day change ±0°

Updated Nov 4, 2026, 7:39 AM EST · Delaware

Wilmington, Delaware. Estimated 2-inch daily average for Nov 3, 2° above normal, steady through Nov 10.

What to do in Wilmington now

Wilmington is in cool-season grass country. Dates are typical for this spot, worked out from 23 years of weather at Wilmington Airport; each status uses this year's soil estimates.

Cool-season: tall fescue, Kentucky bluegrass, perennial ryegrass, fine fescue

  • Crabgrass pre-emergent Closed Apr 4 Typical: Mar 27 – Apr 162-inch soil held 55°F for a week from Apr 4, so crabgrass was sprouting. Next window: about Mar 27 – Apr 16, 2027.
  • Seed or overseed Seed now · last days Typical: Sep 23 – Nov 3The window usually closes by Nov 3, but this fall has kept 4-inch soil at 56°. Seed only if you can keep it moist, and expect slower germination as soil cools.
  • Late-fall feeding Final feeding from about Nov 13 Typical: Nov 13 – Dec 9Not too late. Feed on your normal fall schedule; the last feeding of the year goes down when 4-inch soil falls to about 50°F (typically Nov 13) and before it reaches 40°F (typically Dec 9).

The last 60 days and the week ahead

Wilmington soil is 2° warmer than normal for Nov 3, warmer than on 72% of those dates since 2005, and 2° warmer than a year ago.

The green line is our estimate of the daily average soil temperature 2 inches down, driven by temperatures at Wilmington Airport, 9.3 km from the city center. The dashed part runs the National Weather Service forecast through the same model. Hover or tap for any day.

2-inch soil, estimated From the NWS forecast Normal Normal range (8 years in 10)

30°40°50°60°70°80°90° 50°F55°F Nov 3 Sep 15Oct 1Oct 15Nov 1
Show the numbers
Date2-inch soil4-inch soilAir high / lowNormal (2 in)
Oct 2156°58°66° / 43°57°
Oct 2256°58°70° / 40°57°
Oct 2354°57°62° / 40°56°
Oct 2453°55°65° / 35°56°
Oct 2552°55°69° / 34°56°
Oct 2653°55°71° / 38°55°
Oct 2754°56°69° / 46°55°
Oct 2855°56°68° / 42°55°
Oct 2955°57°71° / 44°54°
Oct 3057°58°74° / 50°54°
Oct 3155°57°62° / 38°53°
Nov 154°56°66° / 38°53°
Nov 253°55°65° / 39°52°
Nov 354°56°72° / 40°52°
Nov 4 (forecast)58°58°75° / 59°51°
Nov 5 (forecast)61°61°74° / 62°51°
Nov 6 (forecast)61°61°71° / 52°51°
Nov 7 (forecast)59°60°65° / 44°51°
Nov 8 (forecast)57°58°61° / 42°50°
Nov 9 (forecast)55°57°60° / 40°50°
Nov 10 (forecast)54°56°64° / 42°50°
Close view of a Kentucky bluegrass lawn
Kentucky bluegrass, the most common cool-season lawn grass in the northern US.

Which grass grows in Wilmington

Wilmington winters are cold enough (January averages 34°F) that cool-season grasses, mostly Kentucky bluegrass, tall fescue and perennial ryegrass, make up most lawns. They grow in spring and fall and slow down in summer heat.

Wilmington soil through the year

Weekly 2-inch estimates for 2026 so far against 2025 and the normal for each week. The red lines mark 50°F, when crabgrass pre-emergent should be down, and 65°F, when warm-season seed sprouts well.

2026 2025 Normal (2005–2025) 8 years in 10

20°30°40°50°60°70°80°90° 50°F65°F 2026 JanFebMarAprMayJunJulAugSepOctNovDec

Normal by month

Month2 in4 inAir
Jan36°37°34°
Feb37°38°36°
Mar43°45°43°
Apr54°55°54°
May64°65°63°
Jun74°75°73°
Jul80°81°78°
Aug78°79°76°
Sep71°73°69°
Oct60°61°57°
Nov47°49°47°
Dec39°40°38°

Soil: average of our daily estimates, 2005–2025. Air: NOAA 1991–2020 normals for the station.

Typical lawn dates in Wilmington

Each date is when the soil estimate (or the air, for freezes) crossed the threshold, year by year since 2005. “Early” and “late” are the 10th and 90th percentile years, so 8 years in 10 fall between them.

EventEarly yearTypicalLate year2026
Last spring freeze (32°F) Mar 27Apr 11Apr 23 Apr 21
Crabgrass model: 250 growing degree days Feb 2Feb 23Mar 10 Mar 6
Pre-emergent window opens (2-inch soil 50°F) Mar 15Mar 27Apr 12 Mar 12
Crabgrass begins to sprout (2-inch soil 55°F) Apr 7Apr 16Apr 26 Apr 4
Cool-season lawns start growing (4-inch soil 55°F) Apr 4Apr 15Apr 26 Apr 4
Warm-season seeding opens (4-inch soil 65°F) May 2May 14May 30 Apr 20
Cool-season seeding opens (4-inch soil under 70°F) Sep 15Sep 23Oct 7 Sep 26
Cool-season seeding ends (4-inch soil under 55°F) Oct 24Nov 3Nov 10 not yet
Warm-season grass goes dormant (4-inch under 55°F) Oct 24Nov 3Nov 10 not yet
First fall freeze (32°F) Oct 31Nov 4Nov 12 not yet
Roots stop feeding (4-inch soil under 40°F) (in 19 of 21 years) Nov 30Dec 9Dec 22 not yet
Large crabgrass with its spreading finger-like seed heads
Large crabgrass in seed. Each plant can drop thousands of seeds that wait for warm spring soil.
A dug soil profile showing layers of silt, loam and clay
A soil profile. The top few inches warm and cool fastest; that is where seeds sprout.

Where these numbers come from

There is no soil sensor in most cities, so we estimate it. Shallow soil follows air temperature with a lag of a few days, and runs a little warmer than the air in fall. We fitted that relationship to 190 USDA soil-sensor stations; on years held out of the fit, the estimate was off by 3.3°F on an average day, and it put the spring 55°F date within a median of 3 days. Read the methodology.

Weather: RCC ACIS station KILG (WILMINGTON AIRPORT), daily data since 1931. Forecast: National Weather Service, PHI office, issued Nov 4, 2026, 4:07 AM EST. Last observed day: Nov 3, 2026.

Wilmington questions

Botanical line drawing of slender crabgrass from 1913
Slender crabgrass, from Britton and Brown, An Illustrated Flora of the Northern United States, 1913.

What is the soil temperature in Wilmington today? Our estimate for Nov 3 is 54°F at 2 inches and 56°F at 4 inches, as a daily average. Early-morning soil runs a few degrees cooler than that, and afternoon soil warmer.

When should I put down crabgrass pre-emergent in Wilmington? Apply when 2-inch soil holds about 50°F and before it holds 55°F. That has typically been Mar 27 to Apr 16 in Wilmington. For 2026 the window closed on Apr 4.

Is it too late to overseed in Wilmington? Seed now · last days. The window usually closes by Nov 3, but this fall has kept 4-inch soil at 56°. Seed only if you can keep it moist, and expect slower germination as soil cools.

Is it too late to fertilize in Wilmington? Final feeding from about Nov 13. Not too late. Feed on your normal fall schedule; the last feeding of the year goes down when 4-inch soil falls to about 50°F (typically Nov 13) and before it reaches 40°F (typically Dec 9).

When is the last frost in Wilmington? The last 32°F night of spring has typically come around Apr 11, and as late as Apr 23 in 1 year in 10. The first fall freeze typically arrives around Nov 4.

Why 2 inches and 4 inches? Crabgrass and most weed seeds sprout in the top inch or two, so pre-emergent timing follows 2-inch soil. Grass seed and roots respond to the slightly steadier soil at about 4 inches.

How accurate is this? It is a model, not a probe in your yard. Expect about 3–4°F of difference on a given day; shade, slope, mulch and irrigation all move real soil. The dates and trends are more reliable than any single day.

Soil near Wilmington today

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