San Antonio Heights, California, sits in USDA hardiness zone 10a — a zone band wide enough that plant choice, not possibility, is the interesting question.
Expect okra, meyer lemon, california poppy, and artichoke to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Even in San Antonio Heights, 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 San Antonio Heights 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 San Antonio Heights — soil, climate, flood, and parcel records. How we handle your address.
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San Antonio Heights — the short answer
San Antonio Heights, California: USDA zone 10a, about 319 days between hard freezes, across 2K acres of town.
- USDA zone
- 10a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Jan 31
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Dec 16
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~319
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 2K 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 10a is San Antonio Heights's average, not your lot's — a low corner or a tree line moves it. Against San Antonio Heights's 319-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in San Antonio Heights
Each reading below is measured for San Antonio Heights itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredSan Antonio Heights runs about 319 days between hard freezes — 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
MeasuredSan Antonio Heights 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 San Antonio Heights is in
San Antonio Heights sits in the Southern California/Northern Baja Coast — EPA Level III, inside the wider Mediterranean California. That is read at San Antonio Heights'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 San Antonio Heights
Every plant below cleared San Antonio Heights's own zone 10a and its 319-day season. Each card opens that plant's California profile. How we score.
Is it too late to plant in San Antonio Heights?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Jan 3; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Jan 31 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 16 — long-season crops need about 90 days of runway, quick greens only 30. In a climate this gentle, “too late” hardly applies — the question becomes which crops prefer the cooler months ahead.
What's on the federal record near San Antonio Heights
Closest first, within ~10 miles of San Antonio Heights. Listing isn't leaking, and distance isn't exposure.
- SAN BERNARDINO COUNTY DEHSBrownfields · 600 ft
- LINDA HOLLISBrownfields · 2300 ft
- SAN BERNARDINO COUNTY FIRE STATION 12Brownfields · 0.5 mi
- UPLAND FUEL INCBrownfields · 0.5 mi
- UPLAND FUEL, INC.Underground Storage Tanks · 0.5 mi
- SHELL SERVICE STATIONBrownfields · 0.6 mi
- MICHAEL AND LOU BRUCEBrownfields · 0.7 mi
- JUDY SCHROEDERBrownfields · 0.8 mi
- JAFAR KAMYABBrownfields · 0.8 mi
- PATRICIA CASILLASBrownfields · 0.8 mi
- YEGOR KAMEMSKIBrownfields · 0.8 mi
- AL BUFFINGTONBrownfields · 0.9 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from San Antonio Heights'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 San Antonio Heights.
Total Sites
4,608
within ~10 miles of San Antonio Heights
Risk Level
Elevated
Highest-severity
27 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of San Antonio Heights
Severity Distribution
within ~10 miles of San Antonio Heights
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around San Antonio Heights, Brownfields runs higher than the national average — 4,109 sites within ~10 miles of San Antonio Heights. 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 San Antonio Heights
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 San Antonio Heights average
Your land is one point inside San Antonio Heights
Everything above resolves to San Antonio Heights as a whole — one PHZM band and one 28°F frost record, read across 2K 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 San Antonio Heights Average
San Antonio Heights Average
- ●USDA Zones 10a, averaged across San Antonio Heights
- ●One soil character for all of San Antonio Heights
- ●Frost dates read at San Antonio Heights's scale: Jan 31 to Dec 16
YOUR Parcel
- ✓Your exact zone, not San Antonio Heights's 10a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in San Antonio Heights
Pull a site-specific report for your exact address in San Antonio Heights, California — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that San Antonio Heights averages can't show:
We read public map data around San Antonio Heights — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the San Antonio Heights average
How we know this about San Antonio Heights
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 San Antonio Heights’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 San Antonio Heights
When does frost risk typically end in San Antonio Heights?
The last hard freeze (28°F) in San Antonio Heights typically lands around Jan 31, 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 21.
When is the first frost in San Antonio Heights?
The first hard freeze (28°F) in San Antonio Heights typically arrives around Dec 16, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Dec 2, so the watching starts about Nov 16 — about 319 days after the spring freeze cleared.
How long is the growing season in San Antonio Heights?
Measured between 28°F hard freezes, San Antonio Heights sees about 319 frost-free days — roughly Jan 31 through Dec 16, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 21 to Dec 2, about 284 days.
Is the soil safe to grow vegetables in San Antonio Heights?
The federal record around San Antonio Heights is a meaningful one — 4,608 documented sites, mostly Brownfields entries (4,109), the nearest Brownfields record about 0.1 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 San Antonio Heights?
From about Nov 16 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 16 (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 16. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at San Antonio Heights's scale — its 10a band and its 319-day season. Your yard writes its own version of San Antonio Heights'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 San Antonio Heights’s own scale
6 of the readings below were taken at San Antonio Heights's own scale — its own ~319-day season between 28°F freezes, the 1,565 acres it covers and 4,608 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- San Antonio Heights's own USDA hardiness band, zones 10aUSDA PHZM 2023
- San Antonio Heights's own 28°F hard-freeze dates, about Jan 31 and Dec 16 and the ~319-day span between themNOAA 1991–2020 Climate Normals
- 4,608 documented contamination sites on the federal record near San Antonio Heights, the closest Brownfields record about 0.1 miles out from the town centreFederal environmental registers
- San Antonio Heights's boundary and the 1,565 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 10a and a ~319-day seasonGrowable Ground crop-matching engine
- San Antonio Heights sits in the Southern California/Northern Baja Coast — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so San Antonio Heights's 1,565 acres read through its county's SSURGO summaryfrom San Bernardino County
- 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 San Antonio Heights's 1,565 acreswhy one lot differs from the next →
- Which side of San Antonio Heights you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,565 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 0.1 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 San Antonio Heights-wide figureread your own land →
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