Warm Springs, California, sits in USDA hardiness zone 9b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
The conditions favor okra, meyer lemon, california poppy, and artichoke, among others — though every individual site edits that list with its own soil, sun, and drainage.
Even in Warm Springs, 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 Warm Springs 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 Warm Springs — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Warm Springs — the short answer
Warm Springs, California: USDA zone 9b, about 303 days between hard freezes, across 897 acres of town.
- USDA zone
- 9b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 13
- Riverside County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 13
- Riverside County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~303
- Riverside County normal — NOAA 1991–2020, nearest to this town
- Town area
- 897 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 Riverside County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9b is Warm Springs's average, not your lot's — a low corner or a tree line moves it. Against Warm Springs's 303-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Warm Springs
Each reading below is measured for Warm Springs itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsWarm Springs runs about 303 days between hard freezes (read from Riverside County, the closest normal to Warm Springs) — 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
MeasuredWarm Springs 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 Warm Springs is in
Warm Springs sits in the Southern California/Northern Baja Coast — EPA Level III, inside the wider Mediterranean California. That is read at Warm Springs's own centroid, and it is not what its county reads: Riverside County is mostly Sonoran Basin and Range. The wider page above you is answering a different question about different ground.
What Grows in Warm Springs
Every plant below cleared Warm Springs's own zone 9b and its 303-day season. Each card opens that plant's California profile. How we score.
Is it too late to plant in Warm Springs?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Jan 16; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 13 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 13 — long-season crops need about 90 days of runway, quick greens only 30. Here the calendar nearly circles: cool-season crops take the winter shift, and the next window is always close.
What's on the federal record near Warm Springs
Closest first, within ~10 miles of Warm Springs. Listing isn't leaking, and distance isn't exposure.
- A LUA WOOD RECYCLING DBA A LUA TRUCKINGBrownfields · 950 ft
- PTI SAND & GRAVEL INCBrownfields · 2000 ft
- ROGUE ENTERPRISE LLCBrownfields · 2000 ft
- C & S MACHINE INCBrownfields · 2300 ft
- HOYT TRANSPORTATION INCBrownfields · 2400 ft
- LAKESIDE 74 INCBrownfields · 0.5 mi
- LAKESIDE CAR RENTAL REPAIR SALEBrownfields · 0.6 mi
- CALTRANS DISTRICT 8 ELSINOREBrownfields · 0.6 mi
- KAIMER TRUCKINGBrownfields · 0.7 mi
- PETSMART #1362Brownfields · 0.7 mi
- SAREC INC DBA GROCERY OUTLET OF LK ELSINOREBrownfields · 0.7 mi
- TURBOSCAPE INCBrownfields · 0.7 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Warm Springs'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 Warm Springs.
Total Sites
1,038
within ~10 miles of Warm Springs
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Warm Springs
Severity Distribution
within ~10 miles of Warm Springs
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Warm Springs, Brownfields runs higher than the national average — 759 sites within ~10 miles of Warm Springs. It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around 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 Warm Springs
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 Warm Springs average
Your land is one point inside Warm Springs
Everything above resolves to Warm Springs as a whole — one PHZM band, read across 897 acres, with hard-freeze dates borrowed from Riverside 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 Warm Springs Average
Warm Springs Average
- ●USDA Zones 9b, averaged across Warm Springs
- ●One soil character for all of Warm Springs
- ●Frost dates read at Warm Springs's scale: Feb 13 to Dec 13
YOUR Parcel
- ✓Your exact zone, not Warm Springs's 9b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Warm Springs
Pull a site-specific report for your exact address in Warm Springs, California — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Warm Springs averages can't show:
We read public map data around Warm Springs — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Warm Springs average
How we know this about Warm Springs
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 Riverside 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 Warm Springs
When does frost risk typically end in Warm Springs?
The last hard freeze (28°F) in Warm Springs typically lands around Feb 13, 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 Mar 6.
When is the first frost in Warm Springs?
The first hard freeze (28°F) in Warm Springs typically arrives around Dec 13, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 29, so the watching starts about Nov 13 — about 303 days after the spring freeze cleared.
How long is the growing season in Warm Springs?
Measured between 28°F hard freezes, Warm Springs sees about 303 frost-free days — roughly Feb 13 through Dec 13, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 6 to Nov 29, about 268 days.
Is the soil safe to grow vegetables in Warm Springs?
The federal record around Warm Springs is a meaningful one — 1,038 documented sites, mostly Brownfields entries (759), the nearest Brownfields record about 0.2 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 Warm Springs?
From about Nov 13 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 13 (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 13. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Warm Springs's scale — its 9b band and its 303-day season. Your yard writes its own version of Warm Springs'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 Warm Springs’s own scale
5 of the readings below were taken at Warm Springs's own scale — the 897 acres it covers and 1,038 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Warm Springs's own USDA hardiness band, zones 9bUSDA PHZM 2023
- 1,038 documented contamination sites on the federal record near Warm Springs, the closest Brownfields record about 0.2 miles out from the town centreFederal environmental registers
- Warm Springs's boundary and the 897 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9b and a ~303-day seasonGrowable Ground crop-matching engine
- Warm Springs 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 — Warm Springs has no normal of its own, so its county's is the closest measured readfrom Riverside County
- Soil character — no town-scale survey exists, so Warm Springs's 897 acres read through its county's SSURGO summaryfrom Riverside County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Riverside 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 Riverside County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Warm Springs's 897 acreswhy one lot differs from the next →
- Which side of Warm Springs you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 897 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 0.2 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 Warm Springs-wide figureread your own land →