Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 30, 2026

Planting zone for Washington, DC

Washington, DC is in USDA zones 7b to 8a across its 266 ZIP codes. The median last spring frost is March 29 and the first fall frost November 8.

Washington on the zone map

Outlined: its 52 ZIP code areas · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zones7b–8a5 to 15 °F

ZIP codes266

Last frostMar 29

First frostNov 8

Growing season224 days

7b 39 ZIPs 8a 227 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

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Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in Washington, DC

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostMarch 29median — 50% chance of a later frost

Safe for tender plantsApril 11only 10% chance of frost after

First fall frostNovember 8median — 10% chance by Oct 26

Growing season224 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 17 and returns around November 20.

From the NOAA station Natl Arboretum Dc, MD, elevation 49 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in Washington

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 15 – Mar 1

SpinachSow outdoors · Feb 15 – Mar 8

Broccoli, cabbageStart indoors · Jan 18 – Feb 1

Broccoli, cabbageTransplant · Mar 8 – Mar 22

Onion setsPlant outdoors · Mar 1 – Mar 15

PotatoesPlant outdoors · Mar 8 – Mar 22

LettuceSow outdoors · Mar 1 – Mar 15

Carrots, beetsSow outdoors · Mar 8 – Mar 22

TomatoesStart indoors · Feb 1 – Feb 15

TomatoesTransplant · Apr 5 – Apr 19

Peppers, eggplantStart indoors · Jan 18 – Feb 1

Peppers, eggplantTransplant · Apr 12 – Apr 26

BeansSow outdoors · Apr 5 – Apr 19

Sweet cornSow outdoors · Apr 5 – Apr 19

Cucumbers, squashSow outdoors · Apr 5 – Apr 19

Fall lettuce, spinachSow outdoors · Sep 13 – Sep 27

GarlicPlant cloves · Oct 25 – Nov 29

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 29) and first fall frost (Nov 8) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 20436 came on Mar 8 — about the same time as the 1991–2020 average (Mar 9).

average
Mar 92026
Mar 8

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 7b in District of Columbia

420 plants native to the lower 48 states, recorded in District of Columbia, and rated by the USDA to survive 5 °F or colder — the bottom of zone 7b. Each links to its USDA PLANTS profile.

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Washington, DC.

Soil in Washington, DC

The center of ZIP 20436 is mapped as Urban land: built-over ground without natural soil data. Garden soil here is usually imported or disturbed — test before you plant.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 20436; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Washington, DC

Summer high90 °Faverage high, July

Winter low28 °Faverage low, January

Hot days48days a year at 90 °F or more

Freezing nights84nights a year at 32 °F or less

Growing degree days4,518base 50 °F — the season’s usable heat

Longest day14 h 54 mindaylight on June 21

Shortest day9 h 26 mindaylight on December 21

Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully

Precipitation45.6 inper year, rain and melted snow

Snowfall10 inper year; 12 days with snow on the ground

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Natl Arboretum Dc, MD (3 mi away); precipitation: Natl Arboretum Dc, MD (3 mi away). Daylight is calculated from latitude.

Planting zone for Washington, DC

Washington on the zone map

Frost forecast — next 7 nights

Frost dates in Washington, DC

When to plant vegetables in Washington

When spring arrived in 2026

Native plants for zone 7b in District of Columbia

Trees 59

Shrubs 78

Wildflowers & perennials 142

Grasses 120

Vines 9

Soil in Washington, DC

Climate in Washington, DC

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

ZIP codes in Washington

Questions about Washington