Big Pool, Maryland, sits in USDA hardiness zone 7a — a zone band wide enough that plant choice, not possibility, is the interesting question.
A short list that earns its place here — cabbage, hazelnut, california poppy, and collard greens — with any one site's soil, sun, and drainage making the final cut.
Even in Big Pool, 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 Big Pool 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 Big Pool — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Big Pool — the short answer
Big Pool, Maryland: USDA zone 7a, about 215 days between hard freezes, across 69 acres of town.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 3
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 4
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~215
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 69 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 7a is Big Pool's average, not your lot's — a low corner or a tree line moves it. Against Big Pool's 215-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Big Pool
Each reading below is measured for Big Pool itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredBig Pool runs about 215 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
MeasuredBig Pool sits in USDA hardiness zone 7a.
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 Big Pool is in
Big Pool sits in the Ridge and Valley — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Big Pool's own centroid rather than borrowed from Washington County.
What Grows in Big Pool
Every plant below cleared Big Pool's own zone 7a and its 215-day season. Each card opens that plant's Maryland profile. How we score.
Is it too late to plant in Big Pool?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Mar 6; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 3 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 4 — 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 Big Pool
Spotted lanternfly documented 1 miles from Big Pool, first recorded 2022. What to watch for.
What's on the federal record near Big Pool
Closest first, within ~10 miles of Big Pool. Listing isn't leaking, and distance isn't exposure.
- MDOT SHA BRIDGE # 2109600Brownfields · 500 ft
- WA Be 5Nitrate · 700 ft
- EXXON - BIG POOLBrownfields · 800 ft
- A.C. & T. - Big Pool ExxonUnderground Storage Tanks · 800 ft
- Caton's GroceryUnderground Storage Tanks · 1700 ft
- CSX TRANSPORTATION INCUnderground Storage Tanks · 0.7 mi
- Fort Frederick State ParkUnderground Storage Tanks · 0.9 mi
- WA Be 24Nitrate · 1.1 mi
- Holloway Construction Co.Underground Storage Tanks · 1.3 mi
- Ber-0546Nitrate · 1.4 mi
- WA Be 29Nitrate · 1.6 mi
- Melton PropertyUnderground Storage Tanks · 1.6 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Big Pool'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 Big Pool.
Total Sites
317
within ~10 miles of Big Pool
Risk Level
Elevated
Highest-severity
4 Toxics Release Inventory facilities
Sources Checked
within ~10 miles of Big Pool
Severity Distribution
within ~10 miles of Big Pool
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Big Pool, two things run higher than the national average within ~10 miles of Big Pool — Nitrate (178 sites) and CAFO (3 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
CAFO: CAFOs pose a different contamination profile than chemical sources.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Check your specific parcel in Big Pool
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 Big Pool average
Your land is one point inside Big Pool
Everything above resolves to Big Pool as a whole — one PHZM band and one 28°F frost record, read across 69 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 Big Pool Average
Big Pool Average
- ●USDA Zones 7a, averaged across Big Pool
- ●One soil character for all of Big Pool
- ●Frost dates read at Big Pool's scale: Apr 3 to Nov 4
YOUR Parcel
- ✓Your exact zone, not Big Pool's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Big Pool
Pull a site-specific report for your exact address in Big Pool, Maryland — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Big Pool averages can't show:
We read public map data around Big Pool — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Big Pool average
How we know this about Big Pool
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 Big Pool’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 Big Pool
When does frost risk typically end in Big Pool?
The last hard freeze (28°F) in Big Pool typically lands around Apr 3, 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 24.
When is the first frost in Big Pool?
The first hard freeze (28°F) in Big Pool typically arrives around Nov 4, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 21, so the watching starts about Oct 5 — about 215 days after the spring freeze cleared.
How long is the growing season in Big Pool?
Measured between 28°F hard freezes, Big Pool sees about 215 frost-free days — roughly Apr 3 through Nov 4, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 24 to Oct 21, about 180 days.
Is the soil safe to grow vegetables in Big Pool?
The federal record around Big Pool is a meaningful one — 317 documented sites, mostly Nitrate entries (178), the nearest Brownfields record under a tenth of a mile 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 Big Pool?
From about Oct 5 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 4 (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 4. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Big Pool's scale — its 7a band and its 215-day season. Your yard writes its own version of Big Pool'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 Big Pool’s own scale
7 of the readings below were taken at Big Pool's own scale — its own ~215-day season between 28°F freezes, the 69 acres it covers and 317 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Big Pool's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Big Pool's own 28°F hard-freeze dates, about Apr 3 and Nov 4 and the ~215-day span between themNOAA 1991–2020 Climate Normals
- 317 documented contamination sites on the federal record near Big Pool, the closest Brownfields record under a tenth of a mile out from the town centreFederal environmental registers
- Big Pool's boundary and the 69 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~215-day seasonGrowable Ground crop-matching engine
- The ecoregion at Big Pool's own centroid, the Ridge and ValleyUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Big Poollydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Big Pool's 69 acres read through its county's SSURGO summaryfrom Washington County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Washington 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 Washington County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Big Pool's 69 acreswhy one lot differs from the next →
- Which side of Big Pool you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 69 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record under a tenth of a mile 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 Big Pool-wide figureread your own land →