Clayton, Delaware, sits in USDA hardiness zones 6a-7b — a zone band wide enough that plant choice, not possibility, is the interesting question.
Well-matched crops include tomato, sweet corn, peach, and blueberry, and the gap between "grows in the area" and "grows in your yard" is closed by soil, sun, and drainage.
Even in Clayton, no two yards are alike.
A low spot, a south-facing slope, or a stand of trees moves the frost date and sun across a single Clayton lot. Enter your address and we'll score 1,112 plants against your land's actual soil, sun, and frost.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Quick Facts
USDA Zones
6a-7b
Last Hard Freeze (28°F)
Mar 10
Town normal — light frosts run a few weeks later
First Hard Freeze (28°F)
Dec 7
Town normal — light frosts arrive a few weeks earlier
Town Area
1K acres
Hardiness Zone Range
Zone maps are averages across Clayton. Your yard's slope, trees, and frost pockets shift what actually grows — see your land's exact reading.
Soil varies lot by lot — soil types explained.
What Grows in Clayton
Plants matched to Clayton's USDA zones 6a-7b — each links to its full growing profile.





Is it too late to plant in Clayton?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Feb 10; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 10 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 7 — long-season crops need about 90 days of runway, quick greens only 30. In a climate this gentle, “too late” hardly applies — the question becomes which crops prefer the cooler months ahead.

Growing Challenges in Delaware
What an experienced grower plans around here — each one has a move.

Sandy soils in southern DE drain too quickly
Organic matter is the fix, applied annually — compost and cover crops teach sandy ground to hold water and nutrients.

Salt spray damage near the coast
Salt-tolerant species up front and a windbreak line behind — a layered coastal defense that catches the spray.

Rising water tables in low-lying areas
Where the water table rises, grow up: mounded rows and raised beds keep roots out of saturated ground.
For cultivar selection, pest pressure, and planting-time guidance specific to Delaware, the University of Delaware Cooperative Extension is the authoritative local source.
Environmental Intelligence
Understanding what's nearby helps you make informed decisions about where and how to grow.
Sources Checked
within ~10 miles of Clayton
Severity Distribution
within ~10 miles of Clayton
Highest-Severity Sites

A note from Gnorman
What an experienced grower watches for around here
In and around Clayton, Nitrate runs higher than the national average — 268 sites nearby. Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Clayton
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,112 plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Your Specific Parcel Matters
Clayton Average
- ●USDA Zones 6a-7b
- ●Generic soil type for the area
- ●State-average frost dates
YOUR Parcel
- ✓Your exact hardiness zone
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Clayton
Pull a site-specific report for your exact address in Clayton, Delaware — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Key Growing Facts for Clayton, Delaware
- USDA Hardiness Zones: 6a-7b (USDA PHZM 2023)
- Last Hard Freeze (28°F): Mar 10 (town normal, NOAA 1991–2020 Climate Normals — light frosts can follow for a few weeks)
- First Hard Freeze (28°F): Dec 7 (town normal, NOAA 1991–2020 Climate Normals — light frosts can arrive a few weeks earlier)
- Days Between Hard Freezes: ~272 (town normal, NOAA 1991–2020 Climate Normals)
- Land Area: 1K acres (US Census TIGER 2025)
Zone data: USDA ARS Plant Hardiness Zone Map 2023. Climate data: NOAA NCEI. Boundaries: US Census TIGER/Line 2025.
Frequently Asked Questions
What hardiness zone is Clayton, Delaware?
Clayton sits in USDA hardiness zones 6a-7b, per the USDA Plant Hardiness Zone Map 2023. Zones reflect average annual extreme minimum temperatures from 1991–2020 weather data.
Is it too late to plant in Clayton?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Feb 10; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 10 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 7 — long-season crops need about 90 days of runway, quick greens only 30. In a climate this gentle, “too late” hardly applies — the question becomes which crops prefer the cooler months ahead.
When does frost risk typically end in Clayton?
The last hard freeze (28°F) in Clayton typically lands around Mar 10, per NOAA 1991–2020 climate normals — an earlier marker than the light-frost dates many planting charts quote. That marks the hard freeze, not the last light frost — light frosts can still bite for a few more weeks, so tender transplants usually wait another 2–3 weeks.
When is the first frost in Clayton?
The first hard freeze (28°F) in Clayton typically arrives around Dec 7, per NOAA 1991–2020 climate normals — the point most tender summer crops finish. Lighter frosts usually reach a couple of weeks earlier, so watch the forecast from late summer on and harvest or cover tender plants before the first cold night.
What vegetables grow in Clayton?
Clayton's zones 6a-7b support a wide range — strong performers include Tomato, Sweet Corn, Peach, Blueberry, and Holly. What actually takes on any one site comes down to its soil, sun, and drainage, and we score each plant against the real conditions at your address.
Which hardiness zone is Clayton, really?
Officially, Clayton sits in USDA zones 6a-7b (USDA PHZM 2023) — but a zone is a 30-year average of winter's coldest night across an area, and it can't see any one yard. A south-facing slope, a tree line, or a low frost pocket can shift a single site by half a zone either way, which is why neighboring gardeners often quote different numbers. We read the conditions at your exact address — soil, sun, slope, and frost — and score 1,112 plants against what's actually there.
Is the soil safe to grow vegetables in Clayton?
The federal record around Clayton runs heavier than most — 681 documented sites — so test the soil before planting food in the ground, and raised beds with clean imported soil grow well in the meantime. Even here, proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what's recorded and where.
How do I protect my plants from frost in Clayton?
As the season closes around the first 28°F hard freeze near Dec 7 (NOAA 1991–2020 climate normals), a few moves buy time: cover tender plants with floating row cover or an old sheet on still, clear nights, water the soil the afternoon before a freeze so it holds warmth overnight, and harvest frost-tender crops like tomatoes, peppers, and basil before the first hard night. Hardy greens and root crops shrug off light frost and often sweeten after it, so leave them in.
Everything on this page is a Clayton average. Your yard writes its own version — we read soil, sun, drainage, and frost at your exact address. Try it for 14 days — no card required.
