Antioch, California, 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.
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 Antioch, 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 Antioch 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 Antioch — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Antioch — the short answer
Antioch, California: USDA zone 9b, about 332 days between hard freezes, across 19K acres of city.
- USDA zone
- 9b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Jan 16
- Contra Costa County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 14
- Contra Costa County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~332
- Contra Costa County normal — NOAA 1991–2020, nearest to this town
- City area
- 19K 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 Contra Costa County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9b is Antioch's average, not your lot's — a low corner or a tree line moves it. Against Antioch's 332-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Antioch
Each reading below is measured for Antioch itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsAntioch runs about 332 days between hard freezes (read from Contra Costa County, the closest normal to Antioch) — 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
MeasuredAntioch 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 Antioch is in
Antioch sits in the Central California Foothills and Coastal Mountains — EPA Level III, inside the wider Mediterranean California. That is read at Antioch's own centroid rather than borrowed from Contra Costa County.
What Grows in Antioch
Every plant below cleared Antioch's own zone 9b and its 332-day season. Each card opens that plant's California profile. How we score.
Is it too late to plant in Antioch?
Too late for some crops, right on time for others — a growing season is a sequence, not a deadline. 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 16 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 14 — 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.
Documented around Antioch
Spotted lanternfly documented 29 miles from Antioch, first recorded 2023. What to watch for.
What's on the federal record near Antioch
Closest first, within ~10 miles of Antioch. Listing isn't leaking, and distance isn't exposure.
- JOANN DELUCABrownfields · 1400 ft
- GOLF COURSE PLAZA 76Underground Storage Tanks · 2200 ft
- AUTOZONE #5124Brownfields · 2200 ft
- TOSCO CORPORATION, KERN FRONT PIPELINEBrownfields · 2300 ft
- CVS PHARMACY #4326Brownfields · 2400 ft
- LONE TREE CONVALESCENT HOSPITALBrownfields · 0.5 mi
- SHERWIN WILLIAMS STORE #8251Brownfields · 0.5 mi
- SUTTER BAY HOSPITALS DBA SUTTER DELTA MEDICAL CENTBrownfields · 0.6 mi
- PALMERS PROFESSIONAL PAINTINGBrownfields · 0.6 mi
- THE COMMONS AT DALLAS RANCH MSL LLC DBABrownfields · 0.6 mi
- DELMER P. ICEMANBrownfields · 0.6 mi
- ANTIOCH LONE TREE DENTALBrownfields · 0.6 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Antioch'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 Antioch.
Total Sites
1,229
within ~10 miles of Antioch
Risk Level
Elevated
Highest-severity
7 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Antioch
Severity Distribution
within ~10 miles of Antioch
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Antioch, Brownfields runs higher than the national average — 1,006 sites within ~10 miles of Antioch. 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 Antioch
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 Antioch average
Your land is one point inside Antioch
Everything above resolves to Antioch as a whole — one PHZM band, read across 19K acres, with hard-freeze dates borrowed from Contra Costa 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 Antioch Average
Antioch Average
- ●USDA Zones 9b, averaged across Antioch
- ●One soil character for all of Antioch
- ●Frost dates read at Antioch's scale: Jan 16 to Dec 14
YOUR Parcel
- ✓Your exact zone, not Antioch's 9b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Antioch
Pull a site-specific report for your exact address in Antioch, California — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Antioch averages can't show:
We read public map data around Antioch — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Antioch average
How we know this about Antioch
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 Contra Costa 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 Antioch
When does frost risk typically end in Antioch?
The last hard freeze (28°F) in Antioch typically lands around Jan 16, 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 6.
When is the first frost in Antioch?
The first hard freeze (28°F) in Antioch typically arrives around Dec 14, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 30, so the watching starts about Nov 14 — about 332 days after the spring freeze cleared.
How long is the growing season in Antioch?
Measured between 28°F hard freezes, Antioch sees about 332 frost-free days — roughly Jan 16 through Dec 14, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 6 to Nov 30, about 297 days.
Is the soil safe to grow vegetables in Antioch?
The federal record around Antioch is a meaningful one — 1,229 documented sites, mostly Brownfields entries (1,006), the nearest Brownfields 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 Antioch?
From about Nov 14 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 14 (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 14. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Antioch's scale — its 9b band and its 332-day season. Your yard writes its own version of Antioch'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 Antioch’s own scale
6 of the readings below were taken at Antioch's own scale — the 18,670 acres it covers and 1,229 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Antioch's own USDA hardiness band, zones 9bUSDA PHZM 2023
- 1,229 documented contamination sites on the federal record near Antioch, the closest Brownfields record about 0.3 miles out from the town centreFederal environmental registers
- Antioch's boundary and the 18,670 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9b and a ~332-day seasonGrowable Ground crop-matching engine
- The ecoregion at Antioch's own centroid, the Central California Foothills and Coastal MountainsUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Antiochlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- The 28°F hard-freeze dates — Antioch has no normal of its own, so its county's is the closest measured readfrom Contra Costa County
- Soil character — no town-scale survey exists, so Antioch's 18,670 acres read through its county's SSURGO summaryfrom Contra Costa County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Contra Costa 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 Contra Costa County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Antioch's 18,670 acreswhy one lot differs from the next →
- Which side of Antioch you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 18,670 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields 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 Antioch-wide figureread your own land →