Rancho Cucamonga, California, sits in USDA hardiness zone 10a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Growers here do well with avocado, meyer lemon, tomato, and artichoke — with the usual caveat that any single yard's soil, sun, and drainage cast the deciding vote.
Even in Rancho Cucamonga, 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 Rancho Cucamonga 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 Rancho Cucamonga — soil, climate, flood, and parcel records. How we handle your address.
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Rancho Cucamonga — the short answer
Rancho Cucamonga, California: USDA zone 10a, about 328 days between hard freezes, across 30K acres of city.
- USDA zone
- 10a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Jan 18
- San Bernardino County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 12
- San Bernardino County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~328
- San Bernardino County normal — NOAA 1991–2020, nearest to this town
- City area
- 30K 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 San Bernardino County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 10a is Rancho Cucamonga's average, not your lot's — a low corner or a tree line moves it. Against Rancho Cucamonga's 328-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Rancho Cucamonga
Each reading below is measured for Rancho Cucamonga itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsRancho Cucamonga runs about 328 days between hard freezes (read from San Bernardino County, the closest normal to Rancho Cucamonga) — close to year-round growing.
Frost is rarely the limit here; winter plantings are as real as summer ones, and the harder question is which crops shrug off the summer heat.
Grow cool-season crops through the mild winter, and choose heat-tolerant varieties for the summer beds.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredRancho Cucamonga sits in USDA hardiness zone 10a.
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 Rancho Cucamonga is in
Rancho Cucamonga sits in the Southern California/Northern Baja Coast — EPA Level III, inside the wider Mediterranean California. That is read at Rancho Cucamonga's own centroid, and it is not what its county reads: San Bernardino County is mostly Mojave Basin and Range. The wider page above you is answering a different question about different ground.
What Grows in Rancho Cucamonga
Plants matched to Rancho Cucamonga's USDA zones 10a, 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 Rancho Cucamonga?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Jan 1; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Jan 18 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 12 — long-season crops need about 90 days of runway, quick greens only 30. And with a calendar this mild, the honest answer is that planting barely stops — winter opens seasons colder regions never see.
What's on the federal record near Rancho Cucamonga
Closest first, within ~10 miles of Rancho Cucamonga. Listing isn't leaking, and distance isn't exposure.
- UPLAND DENTAL & ORTHODONTICSBrownfields · 0.5 mi
- EXXONMOBIL OIL CORP NO12009Brownfields · 0.6 mi
- ALBERTSON'S # 6520Brownfields · 0.6 mi
- Circle K Stores Inc. Site # 2709459Underground Storage Tanks · 0.6 mi
- CIRCLE K STORE #2709459Brownfields · 0.6 mi
- VINEYARDS MARKET PLACEBrownfields · 0.6 mi
- CVS PHARMACY # 9723Brownfields · 0.6 mi
- COMFORT CARE DENTAL BRIEN HSU DDSBrownfields · 0.6 mi
- DOLLAR TREE #06007Brownfields · 0.7 mi
- VINEYARDS MARKETPLACE CLEANERSBrownfields · 0.7 mi
- TRADER JOES 217Brownfields · 0.7 mi
- ATOLINO RINENBrownfields · 0.7 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Rancho Cucamonga'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 Rancho Cucamonga.
Total Sites
5,487
within ~10 miles of Rancho Cucamonga
Risk Level
Elevated
Highest-severity
29 Superfund sites
Sources Checked
within ~10 miles of Rancho Cucamonga
Severity Distribution
within ~10 miles of Rancho Cucamonga
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Rancho Cucamonga, Brownfields runs higher than the national average — 4,721 sites within ~10 miles of Rancho Cucamonga. That's not a problem with your land — it's information about it.
Brownfields: Brownfield sites are former commercial or industrial properties where legacy soil contamination (heavy metals, PAHs, petroleum compounds) may persist.
Check EPA brownfield remediation status — many sites have completed cleanup with institutional controls.
Check your specific parcel in Rancho Cucamonga
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 Rancho Cucamonga average
Your land is one point inside Rancho Cucamonga
Everything above resolves to Rancho Cucamonga as a whole — one PHZM band, read across 30K acres, with hard-freeze dates borrowed from San Bernardino County’s record because no 30-year normal resolves at this city’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 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 Rancho Cucamonga Average
Rancho Cucamonga Average
- ●USDA Zones 10a, averaged across Rancho Cucamonga
- ●One soil character for all of Rancho Cucamonga
- ●Frost dates read at Rancho Cucamonga's scale: Jan 18 to Dec 12
YOUR Parcel
- ✓Your exact zone, not Rancho Cucamonga's 10a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Rancho Cucamonga
Pull a site-specific report for your exact address in Rancho Cucamonga, California — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Rancho Cucamonga averages can't show:
We read public map data around Rancho Cucamonga — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Rancho Cucamonga average
How we know this about Rancho Cucamonga
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 San Bernardino 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 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 Rancho Cucamonga
When does frost risk typically end in Rancho Cucamonga?
The last hard freeze (28°F) in Rancho Cucamonga typically lands around Jan 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 Feb 8.
When is the first frost in Rancho Cucamonga?
The first hard freeze (28°F) in Rancho Cucamonga typically arrives around Dec 12, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 28, so the watching starts about Nov 12 — about 328 days after the spring freeze cleared.
How long is the growing season in Rancho Cucamonga?
Measured between 28°F hard freezes, Rancho Cucamonga sees about 328 frost-free days — roughly Jan 18 through Dec 12, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 8 to Nov 28, about 293 days.
Is the soil safe to grow vegetables in Rancho Cucamonga?
The federal record around Rancho Cucamonga is a meaningful one — 5,487 documented sites, mostly Brownfields entries (4,721), the nearest Brownfields record about 0.5 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 Rancho Cucamonga?
From about Nov 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 Dec 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 Dec 12. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Rancho Cucamonga's scale — its 10a band and its 328-day season. Your yard writes its own version of Rancho Cucamonga'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 Rancho Cucamonga’s own scale
4 of the readings below were taken at Rancho Cucamonga's own scale — the 29,766 acres it covers and 5,487 documented sites around it; 6 are borrowed from a wider read, named and linked below.
Measured here
- Rancho Cucamonga's own USDA hardiness band, zones 10aUSDA PHZM 2023
- 5,487 documented contamination sites on the federal record near Rancho Cucamonga, the closest Brownfields record about 0.5 miles out from the town centreFederal environmental registers
- Rancho Cucamonga's boundary and the 29,766 acres inside itUS Census TIGER/Line 2025
- Rancho Cucamonga sits in the Southern California/Northern Baja Coast — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- The 28°F hard-freeze dates — Rancho Cucamonga has no normal of its own, so its county's is the closest measured readfrom San Bernardino County
- Soil character — no town-scale survey exists, so Rancho Cucamonga's 29,766 acres read through its county's SSURGO summaryfrom San Bernardino County
- The candidate plant list — California's curated set, filtered to this zone band and re-ordered by how much margin each has herefrom California
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom San Bernardino County
- The growing challenges every California grower plans around — written at state scale, so they stay on the state guidefrom California
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom San Bernardino County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Rancho Cucamonga's 29,766 acreswhy one lot differs from the next →
- Which side of Rancho Cucamonga you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 29,766 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 0.5 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 Rancho Cucamonga-wide figureread your own land →
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