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

Planting zone for 20068 — Washington, DC

ZIP code 20068 (Washington, District of Columbia County) is in USDA zone 8a: the coldest winter night averages 10 to 15 °F. The median last spring frost is March 24 and the first fall frost November 18.

Where ZIP 20068 is

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.

Zone8a10 to 15 °F
Coldest night−12.2 to −9.4 °C
Last frostMar 24
First frostNov 18
2012 zone7b

Was 7b on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 8a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Washington, DC…

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 24median — 50% chance of a later frost
Safe for tender plantsApril 6only 10% chance of frost after
First fall frostNovember 18median — 10% chance by Nov 5
Growing season241 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 12 and returns around December 3.

From the NOAA station Washington Reagan Airport, VA — 3 miles away, elevation 10 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 20068

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Feb 10 – Feb 24
SpinachSow outdoors · Feb 10 – Mar 3
Broccoli, cabbageStart indoors · Jan 13 – Jan 27
Broccoli, cabbageTransplant · Mar 3 – Mar 17
Onion setsPlant outdoors · Feb 24 – Mar 10
PotatoesPlant outdoors · Mar 3 – Mar 17
LettuceSow outdoors · Feb 24 – Mar 10
Carrots, beetsSow outdoors · Mar 3 – Mar 17
TomatoesStart indoors · Jan 27 – Feb 10
TomatoesTransplant · Mar 31 – Apr 14
Peppers, eggplantStart indoors · Jan 13 – Jan 27
Peppers, eggplantTransplant · Apr 7 – Apr 21
BeansSow outdoors · Mar 31 – Apr 14
Sweet cornSow outdoors · Mar 31 – Apr 14
Cucumbers, squashSow outdoors · Mar 31 – Apr 14
Fall lettuce, spinachSow outdoors · Sep 23 – Oct 7
GarlicPlant cloves · Nov 4 – Dec 9
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 24) and first fall frost (Nov 18) 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 20068 came on Mar 8 — about the same time as the 1991–2020 average (Mar 6).

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 8a in District of Columbia

427 plants native to the lower 48 states, recorded in District of Columbia, and rated by the USDA to survive 10 °F or colder — the bottom of zone 8a. Each links to its USDA PLANTS profile.

Trees 59

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican beech80 ft · blooms mid spring · low shade tolerance · to −44 °FAmerican chestnut115 ft · blooms early summer · high shade tolerance · to −33 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Fbalsam poplar80 ft · blooms late spring · high shade tolerance · to −79 °F

Shrubs 80

Allegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican holly40 ft · blooms mid spring · low shade tolerance · to −20 °FAmerican hornbeam30 ft · blooms mid spring · low shade tolerance · to −34 °FAmerican plum24 ft · blooms mid spring · high shade tolerance · to −38 °F

Wildflowers & perennials 144

American bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °FAmerican vetch1.3 ft · blooms late spring · high shade tolerance · to −38 °FAmerican water horehound1.8 ft · blooms early summer · low shade tolerance · to −38 °FAmerican water plantain0.5 ft · blooms late spring · high shade tolerance · to −33 °F

Grasses 123

arctic brome3 ft · blooms early summer · low shade tolerance · to −33 °FAtlantic mannagrass3 ft · blooms summer · low shade tolerance · to −8 °Fautumn bluegrass1.5 ft · blooms late spring · medium shade tolerance · to −8 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °Fbig bluestem6 ft · blooms summer · high shade tolerance · to −46 °Fblunt broom sedge3 ft · blooms late spring · low shade tolerance · to −28 °F

Vines 9

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Ffrost grape83 ft · blooms late spring · medium shade tolerance · to −23 °Fgraybark grape50 ft · blooms late spring · medium shade tolerance · to −8 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °F

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 20068 is mapped as Udorthents: 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 20068; 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 low30 °Faverage low, January
Hot days40days a year at 90 °F or more
Freezing nights60nights a year at 32 °F or less
Growing degree days4,709base 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
Precipitation41.8 inper year, rain and melted snow
Snowfall14 inper year; 10 days with snow on the ground

Average high and low, by month

20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 45 °F, low 30 °F 45°30° JanFebruary: average high 48 °F, low 32 °F 48°32° FebMarch: average high 57 °F, low 39 °F 57°39° MarApril: average high 68 °F, low 48 °F 68°48° AprMay: average high 77 °F, low 58 °F 77°58° MayJune: average high 85 °F, low 68 °F 85°68° JunJuly: average high 90 °F, low 72 °F 90°72° JulAugust: average high 88 °F, low 71 °F 88°71° AugSeptember: average high 81 °F, low 64 °F 81°64° SepOctober: average high 69 °F, low 52 °F 69°52° OctNovember: average high 58 °F, low 42 °F 58°42° NovDecember: average high 49 °F, low 35 °F 49°35° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 2.86 in precipitation, 4.9 in snowfall 2.9❄5 JanFebruary: 2.62 in precipitation, 5 in snowfall 2.6❄5 FebMarch: 3.50 in precipitation, 2 in snowfall 3.5❄2 MarApril: 3.21 in precipitation 3.2 AprMay: 3.94 in precipitation 3.9 MayJune: 4.20 in precipitation 4.2 JunJuly: 4.33 in precipitation 4.3 JulAugust: 3.25 in precipitation 3.3 AugSeptember: 3.93 in precipitation 3.9 SepOctober: 3.66 in precipitation 3.7 OctNovember: 2.91 in precipitation, 0.1 in snowfall 2.9 NovDecember: 3.41 in precipitation, 1.7 in snowfall 3.4❄2 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Washington Reagan Airport, VA (3 mi away); precipitation: Washington Reagan Airport, VA (3 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 8a.

202288a
Washington, DC · <1 mi
203918a
Washington Navy Yard, DC · <1 mi
203988a
Washington Navy Yard, DC · <1 mi
204058a
Washington, DC · <1 mi
205118a
Washington, DC · <1 mi
569728a
Washington, DC · <1 mi
569018a
Washington, DC · <1 mi
569158a
Washington, DC · <1 mi

All 266 ZIP codes in Washington → · District of Columbia planting zones →

Questions about 20068

What planting zone is ZIP code 20068?

ZIP code 20068 (Washington, DC) is in USDA hardiness zone 8a on the 2023 map: the coldest night of an average winter reaches 10 to 15 °F (−12.2 to −9.4 °C).

When is the last frost in Washington, DC?

The median last spring frost (32 °F) near 20068 is March 24; after April 6 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Washington Reagan Airport station.

When is the first frost in Washington, DC?

The median first fall frost near 20068 is November 18, giving a median frost-free growing season of 241 days.

When should I plant tomatoes in 20068?

Start tomato seeds indoors around Jan 27 – Feb 10 and set transplants outside around Mar 31 – Apr 14, one to three weeks after the median last frost.

How much rain and snow does 20068 get?

About 41.8 inches of precipitation a year and 14 inches of snowfall (NOAA 1991–2020 normals, Washington Reagan Airport station).

How hot do summers get in Washington, DC?

The average high peaks at 90 °F in July, with about 40 days a year at 90 °F or more.

Did spring come early in Washington, DC in 2026?

Spring leaf-out near 20068 came on Mar 8 in 2026, about the same as the 1991–2020 average (Mar 6), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Washington, DC?

Intermediate onions: the longest day near 20068 is 14 h 54 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 20068 change?

Yes. The 2012 USDA map put 20068 in zone 7b; the 2023 map puts it in zone 8a. The newer map uses 1991–2020 data and more weather stations.