Calverton, Maryland, sits in USDA hardiness zone 7b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Reliable performers under these conditions include cabbage, prickly pear, california poppy, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Calverton, no two yards are alike.
A low spot, a south-facing slope, or a stand of trees moves the frost date and sun across a single Calverton lot. 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 Calverton — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Calverton — the short answer
Calverton, Maryland: USDA zone 7b, about 232 days between hard freezes, across 3K acres of town.
- USDA zone
- 7b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 26
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 13
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~232
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 3K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are this town’s own 28°F normals: light frosts run a few weeks past them, and tender transplants usually wait 2–3 weeks after the last hard freeze.
Hardiness Zone Range
Zone 7b is Calverton's average, not your lot's — a low corner or a tree line moves it. Against Calverton's 232-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Calverton
Each reading below is measured for Calverton itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredCalverton runs about 232 days between hard freezes — a long growing season.
There is slack for succession plantings and slow-finishing crops: many vegetables can be sown twice, and the heat-lovers have time to ripen fully.
Plan a second sowing of quick crops after the first comes out, and use the fall window most gardeners let sit idle.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredCalverton sits in USDA hardiness zone 7b.
The zone sets which perennials, shrubs, and fruit trees live through an average winter here — a plant rated for a colder zone is a safe bet, one rated warmer needs winter protection or gets treated as an annual.
Match perennials and fruit to the zone before you buy, so nothing you plant is a gamble against the cold.
USDA PHZM 2023
The kind of country Calverton is in
Calverton sits in the Southeastern Plains — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Calverton's own centroid, and it is not what its county reads: Montgomery County is mostly Northern Piedmont. The wider page above you is answering a different question about different ground.
What Grows in Calverton
Every plant below cleared Calverton's own zone 7b and its 232-day season. Each card opens that plant's Maryland profile. How we score.
Is it too late to plant in Calverton?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Feb 26; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 26 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 13 — 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.
Documented around Calverton
Spotted lanternfly documented 3 miles from Calverton, first recorded 2022. What to watch for.
What's on the federal record near Calverton
Closest first, within ~10 miles of Calverton. Listing isn't leaking, and distance isn't exposure.
- White Oak Armory - Maryland Army National GuardUnderground Storage Tanks · 1700 ft
- Sunoco #0488-5620Underground Storage Tanks · 1800 ft
- ADA CORPBrownfields · 1800 ft
- CHILDREN'S NATIONAL MEDICAL CENTER - TECH HILLBrownfields · 1800 ft
- Silver Spring Medical CenterUnderground Storage Tanks · 1800 ft
- KAISER PERMANENTE MAS - SILVER SPRINGBrownfields · 1800 ft
- KIDDIE KANDIDS #639Brownfields · 2000 ft
- STAPLES THE OFFICE SUPERSTORE EATS, INC #1273Brownfields · 2000 ft
- NEIGHBORCARE - RIDERWOODBrownfields · 2000 ft
- TARGET STORE T1138Brownfields · 2100 ft
- CVS PHARMACY #16502Brownfields · 2100 ft
- MARYLAND MILITARY FACILITYBrownfields · 2300 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Calverton's center, not your beds. Run your own address for what's upwind of you specifically.
Environmental Intelligence
The counts behind that headline — every source type on the record near Calverton.
Sources Checked
within ~10 miles of Calverton
Severity Distribution
within ~10 miles of Calverton
Highest-Severity Sites
Know Before You Grow
- •Underground tanks leak petroleum as they age — near a former filling station, test the soil.
- •Near a brownfield, raised beds of imported soil give your food clean ground.
- •On a private well, test for nitrates: above 10 mg/L the water needs treatment before irrigating.
Check your specific parcel in Calverton
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,086 plant recommendations.
25+ data sources read at your address, not the Calverton average
Your land is one point inside Calverton
Everything above resolves to Calverton as a whole — one PHZM band and one 28°F frost record, read across 3K acres. Your parcel is one point inside that footprint. 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 town 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 local average.
Your Lot vs the Calverton Average
Calverton Average
- ●USDA Zones 7b, averaged across Calverton
- ●One soil character for all of Calverton
- ●Frost dates read at Calverton's scale: Mar 26 to Nov 13
YOUR Parcel
- ✓Your exact zone, not Calverton's 7b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Calverton
Pull a site-specific report for your exact address in Calverton, Maryland — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Calverton averages can't show:
We read public map data around Calverton — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Calverton average
How we know this about Calverton
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this town’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Calverton’s own record; boundaries and acreage from US Census TIGER/Line 2025; the contamination records from the federal sources named in their beats above. Soil is not read at town grain anywhere on this page — there is no town-resolution survey in our data, which is why you will find no soil grid here rather than a statewide one wearing a local label. The resolution ledger below names every figure this page inherited.
Common questions about Calverton
When does frost risk typically end in Calverton?
The last hard freeze (28°F) in Calverton typically lands around Mar 26, 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 16.
When is the first frost in Calverton?
The first hard freeze (28°F) in Calverton typically arrives around Nov 13, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 30, so the watching starts about Oct 14 — about 232 days after the spring freeze cleared.
How long is the growing season in Calverton?
Measured between 28°F hard freezes, Calverton sees about 232 frost-free days — roughly Mar 26 through Nov 13, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 16 to Oct 30, about 197 days.
Is the soil safe to grow vegetables in Calverton?
The federal record around Calverton is a meaningful one — 3,384 documented sites, mostly Underground Storage Tanks entries (1,788), the nearest Underground Storage Tanks record about 0.3 miles out — 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.
How do I protect my plants from frost in Calverton?
From about Oct 14 the job here turns from planting to protecting — the last start even a 30-day crop can finish. As the season closes around the first 28°F hard freeze near Nov 13 (NOAA 1991–2020 climate normals), three moves buy time: row cover or an old sheet over tender plants on still, clear nights; water the soil the afternoon before a freeze, so it holds warmth overnight; and harvest tomatoes, peppers and basil before Nov 13. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Calverton's scale — its 7b band and its 232-day season. Your yard writes its own version of Calverton's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
What this page reads at Calverton’s own scale
7 of the readings below were taken at Calverton's own scale — its own ~232-day season between 28°F freezes, the 2,929 acres it covers and 3,384 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Calverton's own USDA hardiness band, zones 7bUSDA PHZM 2023
- Calverton's own 28°F hard-freeze dates, about Mar 26 and Nov 13 and the ~232-day span between themNOAA 1991–2020 Climate Normals
- 3,384 documented contamination sites on the federal record near Calverton, the closest Underground Storage Tanks record about 0.3 miles out from the town centreFederal environmental registers
- Calverton's boundary and the 2,929 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7b and a ~232-day seasonGrowable Ground crop-matching engine
- Calverton sits in the Southeastern Plains — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Calvertonlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Calverton's 2,929 acres read through its county's SSURGO summaryfrom Montgomery County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Montgomery County
- The growing challenges every Maryland grower plans around — written at state scale, so they stay on the state guidefrom Maryland
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Montgomery County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Calverton's 2,929 acreswhy one lot differs from the next →
- Which side of Calverton you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 2,929 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.3 miles out, measured from the town centrehow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — measured at your address, and averaged away by any Calverton-wide figureread your own land →
More in Maryland
Growing region
Nearby growing guides