What Planting Zones Are in Washington, D.C.?
Washington, D.C. spans USDA hardiness zones 7b to 8a, where the average coldest winter night ranges from 5 °F to 15 °F (−15 °C to −9.4 °C). Zone 8a covers the most ZIP codes, 86%, and zones 7b to 8a together cover 100% of the state.
Bars show each zone's share of the 289 Washington, D.C. ZIP codes in the official 2023 USDA ZIP code table; select a zone for its temperatures and hardy plants.
What Hardiness Zone Are Washington, D.C. Cities In?
Washington is in zone 8a. The table lists the zone, winter low and average frost dates for 1 Washington, D.C. city, using the ZIP code nearest each city center.
| City | ZIP | Zone | Winter low | Last frost | First frost |
|---|---|---|---|---|---|
| Washington | 20001 | 8a | 10 °F to 15 °F | Mar 29 | Nov 8 |
Zone: 2023 USDA ZIP code table for the ZIP code nearest each city's Census center point. Frost dates: 50% (median) dates from the nearest NOAA station, 1991–2020 normals. Cities: the largest Washington, D.C. places by 2024 Census population estimates, spread across the state, plus the largest place in each common zone. Large cities can span two half zones.
Which Parts of Washington, D.C. Are in Each Zone?
Most of Washington, D.C. falls in zone 8a, including Washington. The table lists the largest places in each zone found in the state's ZIP codes.
| Zone | Avg. coldest night | Share of ZIPs | Largest places in this zone |
|---|---|---|---|
| Zone 7b | 5 °F to 10 °F | 14% (41) | Rural ZIP codes only |
| Zone 8a | 10 °F to 15 °F | 86% (248) | Washington |
Places: incorporated places with 1,000+ residents, assigned the zone of the ZIP code nearest their Census center point.
What Do the Hardiness Zones Mean for Washington, D.C. Gardeners?
A Washington, D.C. gardener in zone 8a sees winter lows about 5 °F milder than one in zone 7b, so a shrub or perennial that thrives in one part of the state can die in another. Choose plants rated to your own ZIP code's zone or colder.
Hardiness zones follow latitude, elevation and large bodies of water rather than state lines. Higher ground and inland valleys that trap cold air usually sit in colder half zones, while cities, coasts and large lakes moderate winter lows. Within Washington, D.C., a plant labelled “zones 7–8” survives winter in at least 100% of ZIP codes, but plants at the edge of their range benefit from mulch and a sheltered spot. Enter a ZIP code in the USDA hardiness zone finder by ZIP code to check your exact half zone before buying perennials.
A zone describes winter cold only. Summer heat, humidity, rainfall and soil decide whether a cold-hardy plant thrives, and planting dates for vegetables follow frost dates, not zones: two Washington, D.C. towns in the same zone can have last frosts weeks apart.
What Plants Grow Well Across Washington, D.C.?
233 plants in PlantoScan's catalogue are hardy in every zone from 7b to 8a, the zones that cover 100% of Washington, D.C. ZIP codes. Popular examples include hydrangea, peony and daisy.
Hydrangea
Hydrangea macrophylla
Zone 5 – 9
AI generated
Peony
Paeonia lactiflora
Zone 3 – 8
AI generated
- DaisyBellis perennisPlantoScan
Daisy
Bellis perennis
Zone 4a – 8b
Chrysanthemum
Chrysanthemum morifolium
Zone 5a – 9b
PlantoscanAI generated
Poppy
Papaver somniferum
Zone 3a – 9b
AI generated
Carnation
Dianthus caryophyllus
Zone 5a – 9b
AI generated
Daffodil
Narcissus poeticus
Zone 3 – 8
AI generated
Azalea
Azalea indica
Zone 6a – 9b
AI generated
Arugula
Eruca sativa
Zone 5a – 10b
AI generated
Hardiness ranges come from PlantoScan's plant database; gardeners in Washington, D.C.'s colder or warmer edge zones should check each plant's full range.
When Is the Last Frost in Washington, D.C.?
Across most Washington, D.C. ZIP codes, the average last spring frost falls between March 24 and April 9. Tender vegetables such as tomatoes go out 1 to 2 weeks after the local date.
The last and first frost dates for Washington, D.C. cities include the safer 90% planting date, the fall frost date, growing season length and a tomato planting table for each city.
Frequently Asked Questions
- What planting zone is Washington, D.C.?
- Washington, D.C. spans USDA hardiness zones 7b to 8a on the 2023 USDA Plant Hardiness Zone Map. Zone 8a is the most common, covering 86% of the state's 289 ZIP codes, and zones 7b to 8a together cover 100%.
- What hardiness zone is Washington, Washington, D.C.?
- Washington is in USDA hardiness zone 8a (ZIP 20001), where the average coldest winter night reaches 10 °F to 15 °F. Its average last spring frost is March 29 and its first fall frost November 8.
- What is the coldest hardiness zone in Washington, D.C.?
- Zone 7b (5 °F to 10 °F) is the coldest zone in Washington, D.C., found in 41 ZIP codes. The warmest is zone 8a (10 °F to 15 °F), around Washington.
Zones: 2023 USDA Plant Hardiness Zone Map ZIP code table, USDA Agricultural Research Service and the PRISM Climate Group, Oregon State University, used without changes. Frost dates: NOAA National Centers for Environmental Information, 1991–2020 U.S. Climate Normals. City locations and populations: U.S. Census Bureau Gazetteer files and Vintage 2024 population estimates. PlantoScan is not affiliated with or endorsed by these agencies.