Marlborough, Missouri, sits in USDA hardiness zone 7a — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
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 Marlborough, 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 Marlborough 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 Marlborough — soil, climate, flood, and parcel records. How we handle your address.
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Marlborough — the short answer
Marlborough, Missouri: USDA zone 7a, about 241 days between hard freezes, across 145 acres of town.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 21
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 17
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~241
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 145 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 Marlborough's average, not your lot's — a low corner or a tree line moves it. Against Marlborough's 241-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Marlborough
Each reading below is measured for Marlborough itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredMarlborough runs about 241 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
MeasuredMarlborough 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 Marlborough is in
Marlborough sits in the Interior River Valleys and Hills — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Marlborough's own centroid rather than borrowed from St. Louis County.
What Grows in Marlborough
Every plant below cleared Marlborough's own zone 7a and its 241-day season. Each card opens that plant's Missouri profile. How we score.
Is it too late to plant in Marlborough?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Feb 21; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 21 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 17 — long-season crops need about 90 days of runway, quick greens only 30. Here the season winds down slowly: late sowings, a real autumn harvest, and garlic in the ground before the first hard freeze.
Documented around Marlborough
Survey cells within 31 miles of Marlborough checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 248 miles off. What to watch for.
What's on the federal record near Marlborough
Closest first, within ~10 miles of Marlborough. Listing isn't leaking, and distance isn't exposure.
- SHELL STATIONUnderground Storage Tanks · 150 ft
- PRJ, INC DBA RAYMAN'S AUTO REPAIRUnderground Storage Tanks · 350 ft
- QUIKTRIP #679Underground Storage Tanks · 450 ft
- CVS PHARMACY #2363Brownfields · 500 ft
- SINCLAIR RETAIL #24Underground Storage Tanks · 750 ft
- FAMILY DOLLAR # 8651Brownfields · 1100 ft
- TROJAHN PLUMBINGUnderground Storage Tanks · 1200 ft
- SS 9521Underground Storage Tanks · 1300 ft
- MANOR CHEMICAL COMPANY, INC.Brownfields · 1800 ft
- MANOR CHEMICAL COMPANY, INC.Superfund · 1800 ft
- MULTIMEDIA KSDK INCUnderground Storage Tanks · 1900 ft
- RISCHBIETER AUTOMOTIVE INCUnderground Storage Tanks · 2000 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Marlborough'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 Marlborough.
Sources Checked
within ~10 miles of Marlborough
Severity Distribution
within ~10 miles of Marlborough
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Marlborough, two things run higher than the national average within ~10 miles of Marlborough — Toxics Release Inventory (307 sites) and Superfund (58 sites). That's not a problem with your land — it's information about it.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check your specific parcel in Marlborough
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 Marlborough average
Your land is one point inside Marlborough
Everything above resolves to Marlborough as a whole — one PHZM band and one 28°F frost record, read across 145 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 Marlborough Average
Marlborough Average
- ●USDA Zones 7a, averaged across Marlborough
- ●One soil character for all of Marlborough
- ●Frost dates read at Marlborough's scale: Mar 21 to Nov 17
YOUR Parcel
- ✓Your exact zone, not Marlborough's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Marlborough
Pull a site-specific report for your exact address in Marlborough, Missouri — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Marlborough averages can't show:
We read public map data around Marlborough — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Marlborough average
How we know this about Marlborough
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 Marlborough’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 Marlborough
When does frost risk typically end in Marlborough?
The last hard freeze (28°F) in Marlborough typically lands around Mar 21, 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 11.
When is the first frost in Marlborough?
The first hard freeze (28°F) in Marlborough typically arrives around Nov 17, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 3, so the watching starts about Oct 18 — about 241 days after the spring freeze cleared.
How long is the growing season in Marlborough?
Measured between 28°F hard freezes, Marlborough sees about 241 frost-free days — roughly Mar 21 through Nov 17, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 11 to Nov 3, about 206 days.
Is the soil safe to grow vegetables in Marlborough?
The federal record around Marlborough runs heavier than most — 3,894 documented sites, mostly Underground Storage Tanks entries (2,318), the nearest Underground Storage Tanks record under a tenth of a mile out — so test the soil before planting food in the ground, and raised beds with clean imported soil grow well in the meantime. Even here, proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what's recorded and where.
How do I protect my plants from frost in Marlborough?
From about Oct 18 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 17 (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 17. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Marlborough's scale — its 7a band and its 241-day season. Your yard writes its own version of Marlborough'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 Marlborough’s own scale
7 of the readings below were taken at Marlborough's own scale — its own ~241-day season between 28°F freezes, the 145 acres it covers and 3,894 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Marlborough's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Marlborough's own 28°F hard-freeze dates, about Mar 21 and Nov 17 and the ~241-day span between themNOAA 1991–2020 Climate Normals
- 3,894 documented contamination sites on the federal record near Marlborough, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Marlborough's boundary and the 145 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~241-day seasonGrowable Ground crop-matching engine
- The ecoregion at Marlborough's own centroid, the Interior River Valleys and HillsUS EPA Level III Ecoregions
- Lanternfly survey cells around Marlborough checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Marlborough's 145 acres read through its county's SSURGO summaryfrom St. Louis County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom St. Louis County
- The growing challenges every Missouri grower plans around — written at state scale, so they stay on the state guidefrom Missouri
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom St. Louis County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Marlborough's 145 acreswhy one lot differs from the next →
- Which side of Marlborough you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 145 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks 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 Marlborough-wide figureread your own land →
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