Cool Valley, Missouri, sits in USDA hardiness zone 7a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
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 Cool Valley, 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 Cool Valley 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 Cool Valley — soil, climate, flood, and parcel records. How we handle your address.
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Cool Valley — the short answer
Cool Valley, Missouri: USDA zone 7a, about 247 days between hard freezes, across 293 acres of city.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 18
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 20
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~247
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 293 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 Cool Valley's average, not your lot's — a low corner or a tree line moves it. Against Cool Valley's 247-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Cool Valley
Each reading below is measured for Cool Valley itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredCool Valley runs about 247 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
MeasuredCool Valley 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 Cool Valley is in
Cool Valley sits in the Interior River Valleys and Hills — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Cool Valley's own centroid rather than borrowed from St. Louis County.
What Grows in Cool Valley
Every plant below cleared Cool Valley's own zone 7a and its 247-day season. Each card opens that plant's Missouri profile. How we score.
Is it too late to plant in Cool Valley?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Feb 18; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 18 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 20 — 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 Cool Valley
Survey cells within 31 miles of Cool Valley checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 237 miles off. What to watch for.
What's on the federal record near Cool Valley
Closest first, within ~10 miles of Cool Valley. Listing isn't leaking, and distance isn't exposure.
- LESCO ENTERPRISESUnderground Storage Tanks · 400 ft
- DWIGHT'S MUFFLERUnderground Storage Tanks · 400 ft
- SHELL OIL COUnderground Storage Tanks · 600 ft
- CLARK OIL STORE #259Underground Storage Tanks · 600 ft
- SPIRITS PLUS DISCOUNT TOBACCOUnderground Storage Tanks · 650 ft
- FAMILY DOLLAR # 10307Brownfields · 800 ft
- COOL VALLEY BPUnderground Storage Tanks · 850 ft
- DEBESAI INC DBA MAACO COLLISION REPAIR & AUTO PAINTINGBrownfields · 850 ft
- SOUTH FLORISSANT CONOCOUnderground Storage Tanks · 1600 ft
- CIRCLE K #1628Underground Storage Tanks · 2300 ft
- WALLIS PETROLEUM LC #9022Underground Storage Tanks · 2600 ft
- QUIKTRIP #617Underground Storage Tanks · 0.6 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Cool Valley'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 Cool Valley.
Sources Checked
within ~10 miles of Cool Valley
Severity Distribution
within ~10 miles of Cool Valley
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Cool Valley, Toxics Release Inventory runs higher than the national average — 326 sites within ~10 miles of Cool Valley. 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.
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Check your specific parcel in Cool Valley
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 Cool Valley average
Your land is one point inside Cool Valley
Everything above resolves to Cool Valley as a whole — one PHZM band and one 28°F frost record, read across 293 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 city 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 Cool Valley Average
Cool Valley Average
- ●USDA Zones 7a, averaged across Cool Valley
- ●One soil character for all of Cool Valley
- ●Frost dates read at Cool Valley's scale: Mar 18 to Nov 20
YOUR Parcel
- ✓Your exact zone, not Cool Valley's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Cool Valley
Pull a site-specific report for your exact address in Cool Valley, Missouri — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Cool Valley averages can't show:
We read public map data around Cool Valley — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Cool Valley average
How we know this about Cool Valley
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Cool Valley’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 city grain anywhere on this page — there is no city-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 Cool Valley
When does frost risk typically end in Cool Valley?
The last hard freeze (28°F) in Cool Valley typically lands around Mar 18, 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 8.
When is the first frost in Cool Valley?
The first hard freeze (28°F) in Cool Valley typically arrives around Nov 20, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 6, so the watching starts about Oct 21 — about 247 days after the spring freeze cleared.
How long is the growing season in Cool Valley?
Measured between 28°F hard freezes, Cool Valley sees about 247 frost-free days — roughly Mar 18 through Nov 20, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 8 to Nov 6, about 212 days.
Is the soil safe to grow vegetables in Cool Valley?
The federal record around Cool Valley runs heavier than most — 4,100 documented sites, mostly Underground Storage Tanks entries (2,497), 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 Cool Valley?
From about Oct 21 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 20 (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 20. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Cool Valley's scale — its 7a band and its 247-day season. Your yard writes its own version of Cool Valley'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 Cool Valley’s own scale
7 of the readings below were taken at Cool Valley's own scale — its own ~247-day season between 28°F freezes, the 293 acres it covers and 4,100 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Cool Valley's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Cool Valley's own 28°F hard-freeze dates, about Mar 18 and Nov 20 and the ~247-day span between themNOAA 1991–2020 Climate Normals
- 4,100 documented contamination sites on the federal record near Cool Valley, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Cool Valley's boundary and the 293 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~247-day seasonGrowable Ground crop-matching engine
- The ecoregion at Cool Valley's own centroid, the Interior River Valleys and HillsUS EPA Level III Ecoregions
- Lanternfly survey cells around Cool Valley 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 Cool Valley's 293 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 Cool Valley's 293 acreswhy one lot differs from the next →
- Which side of Cool Valley you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 293 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 Cool Valley-wide figureread your own land →
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