District of Columbia spans USDA hardiness zones 7b-8a, with a growing season of about 254 frost-free days — a long runway that turns one growing season into what colder regions would call two.
Behind the zone label sits the real climate engine: 39-43 inches of annual rainfall, a median of roughly 4,070 growing-degree days (base 50°F), and about 2,452 winter chill hours for tree fruit. The dominant soils run to urban fill, silt loam, clay loam, and sandy loam (Coastal Plain), and their drainage is one of the strongest predictors of which crops take hold and which falter. Reliable performers under these conditions include tomato, fig, crape myrtle, and kale; what your own ground favors still comes down to its soil, sun, and drainage.
Grounded inUSDA PHZM•NOAA Climate Normals•USDA NRCS SSURGO•GDD (PRISM 1991-2020 normals)•Chill hours (PRISM 1991-2020 normals)•EPA FRS•USDA PLANTS•Growable Ground suitability scoring
District of Columbia spans zones 7b-8a, but your yard sits in exactly one — and slope, tree cover, and low spots nudge it further. Enter your address and we'll score 1,086 plants against your land's actual soil, sun, and frost.
We read public map data around District of Columbia — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
District of Columbia: USDA zones 7b-8a, about 254 frost-free days in a typical county, 1 county.
Measured for the whole district — one jurisdiction, no county spread. Tender transplants usually wait 2–3 weeks past the last hard freeze.
Zone 7b-8a is District of Columbia's average, not your lot's — a low corner or a tree line moves it. Against District of Columbia's 254-day season, see what your own ground reads.
The soil types that dominate District of Columbia — how each drains decides more about crop success than almost anything else. Tap any soil to learn what it is and how to work with it. Each photo is a representative profile of that soil type; the named series is where it was documented, which is often another state.
Drainage
Unpredictable — buried rubble can drain like gravel while compacted fill sheds water like pavement, sometimes within the same yard.
What thrives
Plenty, once you know what you are working over: street trees, tough perennials, and productive raised-bed vegetable gardens are the backbone of urban growing.
Drainage
Moderate. Silt holds water well and releases it steadily, though the fine particles can crust after hard rain and compact under traffic.
What thrives
The full vegetable garden does well here, and small grains, corn, and leafy greens are classic silt-loam crops. Its steady moisture suits shallow-rooted plants that dislike drought stress.
Loam tilted toward clay — heavier in the hand, slower to dry, and richer in nutrients than its sandier cousins. Clay particles carry a surface charge that holds fertilizer and minerals where roots can reach them.
Drainage
Slow to moderate. Water lingers in the root zone longer than in loam, which is a gift in dry summers and a challenge in wet springs.
What thrives
Heavy feeders that appreciate steady moisture — brassicas, corn, beans, and many fruit trees. Perennials with strong root systems establish well once they are through the first season.
Drainage
Fast. The sand fraction opens the soil up, so water moves through the root zone quickly and the surface rarely stays soggy. The trade is that nutrients ride out with the water.
What thrives
Root crops love it — carrots, potatoes, radishes, and onions size up cleanly in ground they can push through. Melons, sweet potatoes, asparagus, and most herbs appreciate the warmth and the drainage.
Soil data: USDA NRCS SSURGO · Soil types explained
Plants well-suited to District of Columbia's climate, soils, and growing season — each links to its full growing profile.
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Feb 15; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 15 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 24 — long-season crops need about 90 days of runway, quick greens only 30. With a season this long, “too late” mostly means “switch crops” — second sowings and a full fall garden are the norm, with garlic closing the year.
The plants District of Columbia put its name on — cultural emblems, not growing recommendations.
American Beauty rose
Rosa
Designated 1925.
Scarlet oak
Quercus coccinea
Designated 1960.
Cherry
Designated 2006.
Plants the USDA PLANTS Database documents as native and present in District of Columbia — a real per-state range, not just a zone match. Ordered by how closely each plant’s published hardiness range matches District of Columbia’s zones 7b-8a, so this is a shortlist by climate fit, not a ranking of which plants matter most here. Presence is statewide, so a plant may still be uncommon in your specific county; your state’s Cooperative Extension or a native-plant society is the local authority.
US-native plants whose hardiness range overlaps District of Columbia’s USDA zones 7b-8a but which USDA PLANTS doesn’t map to a single state range here. Zone overlap is a starting filter, not a range map.
What an experienced grower plans around here — each one has a move.
Dense urban siting means small lots, compacted fill soils, and limited sun
Containers and grow bags turn patios and rooftops into productive ground — and imported mix sidesteps fill-soil questions entirely.
Summer heat and humidity promote fungal diseases
Space for airflow, water mornings at the base, and lean on resistant varieties — the extension's humid-summer playbook.
The urban heat-island effect pushes summer temperatures above surrounding suburbs
The city's extra warmth is usable — it stretches the season for heat-lovers; check your true effective zone and plant to it.
For cultivar selection, pest pressure, and planting-time guidance specific to District of Columbia, the UDC Center for Urban Agriculture is the authoritative local source.
Safe to Grow Here?What the federal record shows across District of Columbia — and how to grow with it.
We checked the federal record across District of Columbia — 2,435 documented sites across 6 of the 9 source types we track.
The most significant on record: 50 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
There's a meaningful federal record across District of Columbia — worth a look before you plant food, not a reason to hold back from growing. Proximity to a documented site is information, not a diagnosis of any one yard. A soil test before new food beds is the sensible precaution here, and the map shows exactly which sites sit where, so you can see what's actually near you.
Sources Checked
across District of Columbia
Severity Distribution
across District of Columbia
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around District of Columbia, Superfund runs higher than the national average — 50 sites across District of Columbia. It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
Everything above resolves to District of Columbia as a whole — a footprint spanning USDA zones 7b-8a. Your parcel sits in exactly one of them. Slope, tree cover, a low spot that pools cold air, and what is in the soil are all resolved at the address, and none of them are visible at state scale. That is the honest boundary of this page, and the reason the next step is a reading of your own ground rather than a better statewide average.
State averages sketch the shape. Your soil, sun exposure, drainage, and microclimate decide what actually takes. Pull a site-specific report for your exact parcel.
Enter your address. We read your soil, sun, drainage, and frost dates, then score 1,086 plants against the real conditions on your land.
Three things about your lot that District of Columbia averages can't show:
We read public map data around District of Columbia — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the District of Columbia average
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read per county and aggregated to the state band; the growing season from NOAA Regional Climate Centers ACIS 1991–2020 28°F normals, read at each county’s own record; rainfall from NOAA Climate Normals; soils from USDA NRCS SSURGO; boundaries from US Census TIGER/Line 2025; the contamination record from the federal sources named in that beat above. Where a county carries no record of its own, it is absent from the figure rather than filled in.
District of Columbia spans USDA hardiness zones 7b-8a — which is to say winter's coldest night runs from about 5°F to 15°F depending where in District of Columbia you are, averaged over 1991–2020 (USDA PHZM 2023).
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Feb 15; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 15 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 24 — long-season crops need about 90 days of runway, quick greens only 30. With a season this long, “too late” mostly means “switch crops” — second sowings and a full fall garden are the norm, with garlic closing the year.
The last hard freeze (28°F) in District of Columbia typically lands around Mar 15, per NOAA 1991–2020 climate normals — earlier than the light-frost dates most charts quote. That marks the hard freeze, not the last light frost — lighter frosts keep biting past it, which is why tender transplants here wait until about Apr 5.
District of Columbia's zones 7b-8a support a wide range — strong performers include Tomato, Fig, Crape Myrtle, Kale, and American 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.
Officially, District of Columbia spans USDA zones 7b-8a (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 1,086 plants against what's actually there.
The federal record across District of Columbia is a meaningful one — 2,435 documented sites, mostly Underground Storage Tanks entries (1,305) — so a soil test before new food beds is a sensible precaution here, not a reason to hold back from growing. Remember that proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what sits where.
Start with three facts. District of Columbia spans USDA zones 7b-8a, which sets what survives winter; the last 28°F hard freeze typically clears around Mar 15 (NOAA 1991–2020 climate normals); and 2,435 documented sites sit on the federal record here, so a soil test before food beds is the smart first step. From there, matching plants to your actual soil and sun is the fun part.
Everything above is measured at District of Columbia's scale — its 7b-8a band and its 254-day season. Your yard writes its own version of District of Columbia's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
6 of the readings below were taken at District of Columbia's own scale — the full zone 7b-8a span inside its borders, the 4 soil types that dominate its ground and 2,435 documented sites on its federal record; anything it cannot resolve at this scale is named below.
Measured here
What this page can’t tell you
Explore growing conditions by county — each has its own zone range and land area.
Explore growing conditions by city or town in District of Columbia.
