Roy, Utah, sits in USDA hardiness zone 7a — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Crops well matched to these conditions include cabbage, hazelnut, california poppy, and collard greens — though what thrives on any one site still turns on its specific soil, sun, and drainage.
Even in Roy, 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 Roy 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 Roy — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Roy — the short answer
Roy, Utah: USDA zone 7a, about 218 days between hard freezes, across 5K acres of city.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 29
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 2
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~218
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 5K 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 Roy's average, not your lot's — a low corner or a tree line moves it. Against Roy's 218-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Roy
Each reading below is measured for Roy itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredRoy runs about 218 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
MeasuredRoy 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 Roy is in
Roy sits in the Central Basin and Range — EPA Level III, inside the wider North American Deserts. That is read at Roy's own centroid, and it is not what its county reads: Weber County is mostly Wasatch and Uinta Mountains. The wider page above you is answering a different question about different ground.
What Grows in Roy
Every plant below cleared Roy's own zone 7a and its 218-day season. Each card opens that plant's Utah profile. How we score.
Is it too late to plant in Roy?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Mar 1; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 29 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 2 — 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.
What's on the federal record near Roy
Closest first, within ~10 miles of Roy. Listing isn't leaking, and distance isn't exposure.
- ROY CITY WATER SYSTEMPFAS · 200 ft
- ROYAL GREEN GOLF COURSEUnderground Storage Tanks · 1800 ft
- ROY CITY CORP. VEHICLE SHOPBrownfields · 2600 ft
- (B- 5- 2)14bdc- 2Nitrate · 0.5 mi
- ROY CITY SHOPSUnderground Storage Tanks · 0.6 mi
- (B- 5- 2)10dbc- 1Nitrate · 0.7 mi
- ROY MERCURYSuperfund · 0.9 mi
- ROY HIGH SCHOOLUnderground Storage Tanks · 0.9 mi
- ROY SWITCH YARDUnderground Storage Tanks · 0.9 mi
- TRIPLE STOP PHILLIPS 66Underground Storage Tanks · 0.9 mi
- (B- 5- 2)22bba- 3Nitrate · 0.9 mi
- OLD FARM MARKETUnderground Storage Tanks · 1.0 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Roy'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 Roy.
Sources Checked
within ~10 miles of Roy
Severity Distribution
within ~10 miles of Roy
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Roy, two things run higher than the national average within ~10 miles of Roy — PFAS (19 sites) and Superfund (17 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check your specific parcel in Roy
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 Roy average
Your land is one point inside Roy
Everything above resolves to Roy as a whole — one PHZM band and one 28°F frost record, read across 5K 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 Roy Average
Roy Average
- ●USDA Zones 7a, averaged across Roy
- ●One soil character for all of Roy
- ●Frost dates read at Roy's scale: Mar 29 to Nov 2
YOUR Parcel
- ✓Your exact zone, not Roy's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Roy
Pull a site-specific report for your exact address in Roy, Utah — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Roy averages can't show:
We read public map data around Roy — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Roy average
How we know this about Roy
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 Roy’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 Roy
When does frost risk typically end in Roy?
The last hard freeze (28°F) in Roy typically lands around Mar 29, 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 19.
When is the first frost in Roy?
The first hard freeze (28°F) in Roy typically arrives around Nov 2, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 19, so the watching starts about Oct 3 — about 218 days after the spring freeze cleared.
How long is the growing season in Roy?
Measured between 28°F hard freezes, Roy sees about 218 frost-free days — roughly Mar 29 through Nov 2, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 19 to Oct 19, about 183 days.
Is the soil safe to grow vegetables in Roy?
The federal record around Roy runs heavier than most — 1,158 documented sites, mostly Underground Storage Tanks entries (656), the nearest PFAS 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 Roy?
From about Oct 3 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 2 (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 2. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Roy's scale — its 7a band and its 218-day season. Your yard writes its own version of Roy'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 Roy’s own scale
6 of the readings below were taken at Roy's own scale — its own ~218-day season between 28°F freezes, the 5,215 acres it covers and 1,158 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Roy's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Roy's own 28°F hard-freeze dates, about Mar 29 and Nov 2 and the ~218-day span between themNOAA 1991–2020 Climate Normals
- 1,158 documented contamination sites on the federal record near Roy, the closest PFAS record under a tenth of a mile out from the town centreFederal environmental registers
- Roy's boundary and the 5,215 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~218-day seasonGrowable Ground crop-matching engine
- Roy sits in the Central Basin and Range — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Roy's 5,215 acres read through its county's SSURGO summaryfrom Weber County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Weber 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 Weber County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Roy's 5,215 acreswhy one lot differs from the next →
- Which side of Roy you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 5,215 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest PFAS 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 Roy-wide figureread your own land →
More in Utah
Growing region
Nearby growing guides