Mantua, Utah, sits in USDA hardiness zone 6a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
Well-matched crops include cabbage, blackberry, california poppy, and collard greens, and the gap between "grows in the area" and "grows in your yard" is closed by soil, sun, and drainage.
Even in Mantua, 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 Mantua 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 Mantua — soil, climate, flood, and parcel records. How we handle your address.
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Mantua — the short answer
Mantua, Utah: USDA zone 6a, about 164 days between hard freezes, across 3K acres of town.
- USDA zone
- 6a
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 1
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 12
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~164
- 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 6a is Mantua's average, not your lot's — a low corner or a tree line moves it. Against Mantua's 164-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Mantua
Each reading below is measured for Mantua itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredMantua runs about 164 days between hard freezes — a moderate growing season.
There is room for the full run of cool-season crops plus a warm-season main crop, but the calendar is tight enough that a late spring or early fall frost still decides how much finishes.
Time warm-season transplants to your last hard freeze, and a few weeks of season extension turns a near-miss harvest into a sure one.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredMantua sits in USDA hardiness zone 6a.
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 Mantua is in
Mantua sits in the Wasatch and Uinta Mountains — EPA Level III, inside the wider Northwestern Forested Mountains. That is read at Mantua's own centroid, and it is not what its county reads: Box Elder County is mostly Central Basin and Range. The wider page above you is answering a different question about different ground.
What Grows in Mantua
Every plant below cleared Mantua's own zone 6a and its 164-day season. Each card opens that plant's Utah profile. How we score.
Is it too late to plant in Mantua?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Apr 3; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 1 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 12 — long-season crops need about 90 days of runway, quick greens only 30. Even past midsummer there is room for a true fall garden here, and garlic planted near the close carries the momentum into next year.
What's on the federal record near Mantua
Closest first, within ~10 miles of Mantua. Listing isn't leaking, and distance isn't exposure.
- COUNTRY STOREUnderground Storage Tanks · 2100 ft
- MANTUA FISH HATCHERYUnderground Storage Tanks · 1.0 mi
- Silver EagleMining · 1.4 mi
- HoltonMining · 2.7 mi
- UDOT STA. #1423Underground Storage Tanks · 3.1 mi
- STAKER PARSON BRIGHAM CITYToxics Release Inventory · 3.4 mi
- BRIGHAM CITY OPERATIONSBrownfields · 3.4 mi
- STAKER PARSONS LOCATION # F480901Underground Storage Tanks · 3.6 mi
- UDOT # 148 SARDINE SUMMITUnderground Storage Tanks · 3.7 mi
- STAKER & PARSON COMPANIES/FIFEToxics Release Inventory · 3.7 mi
- CEMETARY OFFICEUnderground Storage Tanks · 3.8 mi
- BARON WOOLEN MILLS INC.Underground Storage Tanks · 3.8 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Mantua'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 Mantua.
Total Sites
162
within ~10 miles of Mantua
Risk Level
High
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Mantua
Severity Distribution
within ~10 miles of Mantua
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Mantua, two things run higher than the national average within ~10 miles of Mantua — Mining (34 sites) and PFAS (3 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Mining: Mining sites — both historic and active — can leach heavy metals (arsenic, lead, cadmium, mercury) into soil and water for centuries after operations cease.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check your specific parcel in Mantua
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 Mantua average
Your land is one point inside Mantua
Everything above resolves to Mantua 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 Mantua Average
Mantua Average
- ●USDA Zones 6a, averaged across Mantua
- ●One soil character for all of Mantua
- ●Frost dates read at Mantua's scale: May 1 to Oct 12
YOUR Parcel
- ✓Your exact zone, not Mantua's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Mantua
Pull a site-specific report for your exact address in Mantua, Utah — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Mantua averages can't show:
We read public map data around Mantua — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Mantua average
How we know this about Mantua
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 Mantua’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 Mantua
When does frost risk typically end in Mantua?
The last hard freeze (28°F) in Mantua typically lands around May 1, 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 May 22.
When is the first frost in Mantua?
The first hard freeze (28°F) in Mantua typically arrives around Oct 12, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 28, so the watching starts about Sep 12 — about 164 days after the spring freeze cleared.
How long is the growing season in Mantua?
Measured between 28°F hard freezes, Mantua sees about 164 frost-free days — roughly May 1 through Oct 12, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 22 to Sep 28, about 129 days.
Is the soil safe to grow vegetables in Mantua?
The federal record around Mantua runs heavier than most — 162 documented sites, mostly Underground Storage Tanks entries (76), the nearest Underground Storage Tanks record about 0.4 miles 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 Mantua?
From about Sep 12 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 Oct 12 (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 Oct 12. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Mantua's scale — its 6a band and its 164-day season. Your yard writes its own version of Mantua'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 Mantua’s own scale
6 of the readings below were taken at Mantua's own scale — its own ~164-day season between 28°F freezes, the 3,121 acres it covers and 162 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Mantua's own USDA hardiness band, zones 6aUSDA PHZM 2023
- Mantua's own 28°F hard-freeze dates, about May 1 and Oct 12 and the ~164-day span between themNOAA 1991–2020 Climate Normals
- 162 documented contamination sites on the federal record near Mantua, the closest Underground Storage Tanks record about 0.4 miles out from the town centreFederal environmental registers
- Mantua's boundary and the 3,121 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6a and a ~164-day seasonGrowable Ground crop-matching engine
- Mantua sits in the Wasatch and Uinta Mountains — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Mantua's 3,121 acres read through its county's SSURGO summaryfrom Box Elder County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Box Elder County
- The growing challenges every Utah grower plans around — written at state scale, so they stay on the state guidefrom Utah
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Box Elder County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Mantua's 3,121 acreswhy one lot differs from the next →
- Which side of Mantua you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 3,121 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.4 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 Mantua-wide figureread your own land →
More in Utah
Wider growing context
What grows across UtahMantua sits outside our named growing regions, so Utah as a whole is its closest context here.
Nearby growing guides