Topock, Arizona, sits in USDA hardiness zone 9b — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
Well-matched crops include jalapeno, palo verde, date palm, and prickly pear, and the gap between "grows in the area" and "grows in your yard" is closed by soil, sun, and drainage.
Even in Topock, 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 Topock 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 Topock — soil, climate, flood, and parcel records. How we handle your address.
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Topock — the short answer
Topock, Arizona: USDA zone 9b, about 242 days between hard freezes, across 166 acres of town.
- USDA zone
- 9b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 21
- Mohave County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Nov 18
- Mohave County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~242
- Mohave County normal — NOAA 1991–2020, nearest to this town
- Town area
- 166 acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. No 30-year normal resolves at this town’s own centroid, so the hard-freeze dates are Mohave County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9b is Topock's average, not your lot's — a low corner or a tree line moves it. Against Topock's 242-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Topock
Each reading below is measured for Topock itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsTopock runs about 242 days between hard freezes (read from Mohave County, the closest normal to Topock) — 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
MeasuredTopock sits in USDA hardiness zone 9b.
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 Topock is in
Topock sits in the Mojave Basin and Range — EPA Level III, inside the wider North American Deserts. That is read at Topock's own centroid rather than borrowed from Mohave County.
What Grows in Topock
Plants matched to Topock's USDA zones 9b, ordered by how much hardiness margin each has here — the ones with room to spare at both ends of this town's band lead. Each links to its full growing profile.
Is it too late to plant in Topock?
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 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 18 — 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 Topock
Survey cells within 31 miles of Topock checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 189 miles off. What to watch for.
What's on the federal record near Topock
Closest first, within ~10 miles of Topock. Listing isn't leaking, and distance isn't exposure.
- TOPOCK MARINAUnderground Storage Tanks · 1400 ft
- USF&W - HAVASU NATIONAL WILDLIFE REFUGEUnderground Storage Tanks · 1900 ft
- SANTA FE RAILWAY COMPANYUnderground Storage Tanks · 1900 ft
- BUREAU OF RECLAMATIONBrownfields · 0.7 mi
- ARIZONA LNGBrownfields · 0.9 mi
- B-16-21 36CBC1Nitrate · 1.0 mi
- PACIFIC GAS & ELECTRIC TOPOCK COMPRESSOR STATIONBrownfields · 1.0 mi
- USDOI FW - HAVASU NATIONAL WILDLIFE REFUGEUnderground Storage Tanks · 1.6 mi
- TOPOCK GROUNDWATER EXTRACTION SITEBrownfields · 1.8 mi
- PG&E - Topock Compressor StationUnderground Storage Tanks · 1.8 mi
- 007N024E06N001SNitrate · 2.3 mi
- B-16-20H14BCA1Nitrate · 2.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Topock'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 Topock.
Total Sites
58
within ~10 miles of Topock
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Topock
Severity Distribution
within ~10 miles of Topock
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Topock, Mining runs higher than the national average — 6 sites within ~10 miles of Topock. That's not a problem with your land — it's information about it.
Mining: Mining sites — both historic and active — can leach heavy metals (arsenic, lead, cadmium, mercury) into soil and water for centuries after operations cease.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Check your specific parcel in Topock
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 Topock average
Your land is one point inside Topock
Everything above resolves to Topock as a whole — one PHZM band, read across 166 acres, with hard-freeze dates borrowed from Mohave County’s record because no 30-year normal resolves at this town’s own centroid. 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 Topock Average
Topock Average
- ●USDA Zones 9b, averaged across Topock
- ●One soil character for all of Topock
- ●Frost dates read at Topock's scale: Mar 21 to Nov 18
YOUR Parcel
- ✓Your exact zone, not Topock's 9b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Topock
Pull a site-specific report for your exact address in Topock, Arizona — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Topock averages can't show:
We read public map data around Topock — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Topock average
How we know this about Topock
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 Mohave County’s record, because none resolves here; 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 Topock
When does frost risk typically end in Topock?
The last hard freeze (28°F) in Topock 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 Topock?
The first hard freeze (28°F) in Topock typically arrives around Nov 18, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 4, so the watching starts about Oct 19 — about 242 days after the spring freeze cleared.
How long is the growing season in Topock?
Measured between 28°F hard freezes, Topock sees about 242 frost-free days — roughly Mar 21 through Nov 18, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 11 to Nov 4, about 207 days.
Is the soil safe to grow vegetables in Topock?
The federal record around Topock is a meaningful one — 58 documented sites, mostly Brownfields entries (19), the nearest Underground Storage Tanks record about 0.3 miles 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 Topock?
From about Oct 19 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 18 (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 18. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Topock's scale — its 9b band and its 242-day season. Your yard writes its own version of Topock'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 Topock’s own scale
5 of the readings below were taken at Topock's own scale — the 166 acres it covers and 58 documented sites around it; 6 are borrowed from a wider read, named and linked below.
Measured here
- Topock's own USDA hardiness band, zones 9bUSDA PHZM 2023
- 58 documented contamination sites on the federal record near Topock, the closest Underground Storage Tanks record about 0.3 miles out from the town centreFederal environmental registers
- Topock's boundary and the 166 acres inside itUS Census TIGER/Line 2025
- The ecoregion at Topock's own centroid, the Mojave Basin and RangeUS EPA Level III Ecoregions
- Lanternfly survey cells around Topock checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- The 28°F hard-freeze dates — Topock has no normal of its own, so its county's is the closest measured readfrom Mohave County
- Soil character — no town-scale survey exists, so Topock's 166 acres read through its county's SSURGO summaryfrom Mohave County
- The candidate plant list — Arizona's curated set, filtered to this zone band and re-ordered by how much margin each has herefrom Arizona
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Mohave County
- The growing challenges every Arizona grower plans around — written at state scale, so they stay on the state guidefrom Arizona
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Mohave County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Topock's 166 acreswhy one lot differs from the next →
- Which side of Topock you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 166 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.3 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 Topock-wide figureread your own land →
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