Planting zone for 20772 — Upper Marlboro, MD
ZIP code 20772 (Upper Marlboro, Prince George's County) is in USDA zone 7b: the coldest winter night averages 5 to 10 °F. The median last spring frost is April 9 and the first fall frost October 29.
Where ZIP 20772 is
Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoomNot 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.
Was 7a 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 7b means →
Frost forecast — next 7 nights
live from the National Weather ServiceLoading the forecast for Upper Marlboro, MD…
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 Upper Marlboro, MD
A hard freeze (28 °F) usually ends around March 30 and returns around November 10.
From the NOAA station Upper Marlboro 3 Nnw, MD — 5 miles away, elevation 131 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 20772
Counted from the median last spring frost (Apr 9) and first fall frost (Oct 29) 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 20772 came on Mar 11 — about the same time as the 1991–2020 average (Mar 10).
Mar 102026
Mar 11
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 Maryland
618 plants native to the lower 48 states, recorded in Maryland, and rated by the USDA to survive 5 °F or colder — the bottom of zone 7b. Each links to its USDA PLANTS profile.
Trees 83
Shrubs 127
Wildflowers & perennials 206
Grasses 176
Vines 12
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 Upper Marlboro, MD.
Soil in Upper Marlboro, MD
The soil mapped at the center of ZIP 20772 is Udorthents — gravelly sandy loam, well drained.
Map unit: Udorthents, reclaimed gravel pits, 0 to 5 percent slopes.
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 20772; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.
Climate in Upper Marlboro, MD
Average high and low, by month
Precipitation by month inches · ❄ = snowfall
NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Upper Marlboro 3 Nnw, MD (5 mi away); precipitation: Upper Marlboro 3 Nnw, MD (5 mi away). Daylight is calculated from latitude.
Nearby ZIP codes
All 8 nearest ZIP codes share zone 7b.
All 5 ZIP codes in Upper Marlboro → · Maryland planting zones →
Questions about 20772
What planting zone is ZIP code 20772?
ZIP code 20772 (Upper Marlboro, MD) is in USDA hardiness zone 7b on the 2023 map: the coldest night of an average winter reaches 5 to 10 °F (−15 to −12.2 °C).
When is the last frost in Upper Marlboro, MD?
The median last spring frost (32 °F) near 20772 is April 9; after April 24 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Upper Marlboro 3 Nnw station.
When is the first frost in Upper Marlboro, MD?
The median first fall frost near 20772 is October 29, giving a median frost-free growing season of 203 days.
When should I plant tomatoes in 20772?
Start tomato seeds indoors around Feb 12 – Feb 26 and set transplants outside around Apr 16 – Apr 30, one to three weeks after the median last frost.
How much rain and snow does 20772 get?
About 45 inches of precipitation a year and 16 inches of snowfall (NOAA 1991–2020 normals, Upper Marlboro 3 Nnw station).
How hot do summers get in Upper Marlboro, MD?
The average high peaks at 88 °F in July, with about 32 days a year at 90 °F or more.
What kind of soil does 20772 have?
The USDA soil survey maps Udorthents at the center of ZIP 20772: gravelly sandy loam, well drained, pH about 5.0 (strongly acidic).
Did spring come early in Upper Marlboro, MD in 2026?
Spring leaf-out near 20772 came on Mar 11 in 2026, about the same as the 1991–2020 average (Mar 10), according to the USA National Phenology Network Spring Index.
What kind of onions grow in Upper Marlboro, MD?
Intermediate onions: the longest day near 20772 is 14 h 53 min, so day-neutral types bulb best; long-day varieties may not bulb fully.
Did the zone for 20772 change?
Yes. The 2012 USDA map put 20772 in zone 7a; the 2023 map puts it in zone 7b. The newer map uses 1991–2020 data and more weather stations.