Kern County, in California, sits in USDA hardiness zone 9b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
Crops well matched to these conditions include okra, meyer lemon, california poppy, and artichoke — though what thrives on any one site still turns on its specific soil, sun, and drainage.
Kern County lies within the San Joaquin Valley and the California Central Valley — a regional growing area with its own character.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Kern County holds more than one microclimate.
Soils and elevations shift across Kern County, so your frost dates and drainage aren't the county average. 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 Kern County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Kern County — the short answer
Kern County, California: USDA zone 9b, about 319 days between hard freezes, across 5.2M acres.
- USDA zone
- 9b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Jan 23
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Dec 8
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~319
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 5.2M acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are county 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 9b is Kern County's average, not your lot's — a low corner or a tree line moves it. Against Kern County's 319-day season, see what your own ground reads.
One county, several growing seasons
Kern County's hard-freeze record runs about 319 days between freezes — but that is the county-wide average, and several towns inside it carry a markedly different season in their own 30-year record: Glennville at about 218 days, Bodfish at 278, Lake Isabella at 278 and Stallion Springs at 280 (against the county's ~319).
Those are measured records, not estimates. If you garden in one of these pockets, plant against your own town's season rather than the county's ~319-day average.
NOAA Regional Climate Centers ACIS (1991–2020), 30-year daily minimum record. Only held-out towns carrying their own record are named — a town with no record of its own is absent rather than estimated, and a county with nothing qualifying shows no spread at all.
Heat and winter chill in Kern County
Across a year, Kern County accumulates about 5,406 growing degree days above 50°F, about 1,649 more than the middle California county — ahead of 53 of California’s 57 counties. Degree days are the heat a crop actually gets to work with — more of them is more room to ripen a long-season crop before the freeze closes the window.
Winter banks about 979 hours below 45°F, 208 fewer than the California middle of 1,187. Chill is what tells a fruit tree its dormancy is over, and it is set by climate rather than by anything you can build.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Kern County
Across Kern County, the ground is predominantly Entisols, where Cajon, Kimberlina, and Hesperia are the most extensive named soil series. The soil is generally well drained with a sandy loam surface. Topsoil pH runs about 6.5–7.9, neutral. Rainfall drains through hydrologic group D soils.
Soil order
Entisols
Drainage
Well drained
Hydric soils
3%
Soil still varies lot by lot — soil types explained.
How the ground varies across Kern County
The USDA soil survey maps 74% of Kern County as well drained — but another 24% drains differently: 12% somewhat excessively drained, 7% excessively drained.
Cajon is the most extensive named soil at 5% of mapped acres, then Kimberlina (3%) and Hesperia (2%).
Which of them your own lot sits on is a parcel question, not a county one. Check your address for the survey at your boundary.
What this means for growing in Kern County
Each reading below is measured for Kern County itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Drainage
MeasuredThe dominant soils across Kern County are well drained, in hydrologic group D — ground that drains quickly.
The upside is soil you can work early in spring and roots that never drown; the cost is that fast-draining ground dries out fast and leaches nutrients away before plants can use them.
Work in compost and mulch to hold moisture and feed, and water more often in short doses than deep and rarely.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Kern County runs about pH 6.5–7.9, close to neutral.
This is the range most vegetables prefer — one correction you probably do not have to make, which is genuinely good news for a new bed.
Keep it there with compost rather than lime or sulfur, and only amend if your own soil test says otherwise.
USDA NRCS SSURGO
Season length
MeasuredKern County 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
MeasuredKern County 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 Kern County is in
Kern County spans 4 EPA Level III ecoregions — Central California Valley (35%), Mojave Basin and Range (25%), Sierra Nevada (22%) and Central California Foothills and Coastal Mountains (16%). Which one your land falls in changes what grows wild there and how the ground behaves, and a county-wide answer cannot tell you which.
What Grows in Kern County
We scored all 1,086 plants against Kern County's own USDA zone 9b and its own 319-day season between hard freezes, using the same matching engine that runs a full parcel report. These cleared both. Sun, soil pH and drainage vary lot by lot — those are the parcel questions below. Each card opens that plant's California profile.
Is it too late to plant in Kern County?
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 23 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 8 — long-season crops need about 90 days of runway, quick greens only 30. With almost year-round growing weather, timing is about heat and rainfall more than frost — some bench is always in play.
Documented around Kern County
- monarch butterfly29 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Kern County
USGS estimates 1,203,290 lb of Glyphosate on Kern County farmland in 2019, its largest by weight, ahead of Methoxyfenozide (61,508 lb) and Imidacloprid (45,678 lb).
Farmland across the whole county, not any one lot. Check your address for the site-by-site record.
Safe to Grow Here?
What the federal record shows across Kern County — and how to grow with it.
We checked the federal record across Kern County — 8,118 documented sites across 7 of the 9 source types we track.
The most significant on record: 36 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
Kern County carries one of the heavier federal records we track — and that's not a verdict on your yard. Proximity to a documented site is information, not a diagnosis: nothing here says any particular parcel is affected. It does earn one concrete step — before food beds go in the ground, a professional soil test tells you exactly what you're working with, and raised beds with clean imported soil grow well almost anywhere in the meantime.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Kern County
Closest first, across Kern County. Listing isn't leaking, and distance isn't exposure.
- Gem ProspectMining · 0.9 mi
- RECOLOGY ENV BENA LANDFILL OPERATIONSBrownfields · 1.9 mi
- PEED EQUIPMENT COMPANYBrownfields · 1.9 mi
- BAKERSFIELD SHOPBrownfields · 2.0 mi
- 030S030E09F001MNitrate · 2.0 mi
- H & H FARMS INCBrownfields · 2.1 mi
- BAKERSFIELD METROPOLITAN LANDFILL @BENABrownfields · 3.1 mi
- EDISON SAND AND GRAVEL INCBrownfields · 3.1 mi
- 030S030E17G001MNitrate · 3.2 mi
- 030S030E08P001MNitrate · 3.3 mi
- 030S030E06J001MNitrate · 3.7 mi
- Murray Family FarmsUnderground Storage Tanks · 3.8 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Kern County'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 Kern County.
Severity Distribution
across Kern County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Kern County, two things run higher than the national average across Kern County — Nitrate (2,606 sites) and Brownfields (4,706 sites). That's not a problem with your land — it's information about it.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Brownfields: Brownfield sites are former commercial or industrial properties where legacy soil contamination (heavy metals, PAHs, petroleum compounds) may persist.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check EPA brownfield remediation status — many sites have completed cleanup with institutional controls.
Check your specific parcel in Kern County
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 Kern County average
Your land is one point inside Kern County
Everything above resolves to Kern County as a whole — a county whose own towns’ 30-year records run 218 days between freezes in Glennville to 280 in Stallion Springs. Your parcel sits at one point in that range, not in the middle of it. 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 county 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 county average.
Your Lot vs the Kern County Average
Kern County Average
- ●USDA Zones 9b, averaged across Kern County
- ●One soil character for all of Kern County
- ●Frost dates read at Kern County's scale: Jan 23 to Dec 8
YOUR Parcel
- ✓Your exact zone, not Kern County's 9b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Kern County
Pull a site-specific report for your exact address in Kern County, California — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Kern County averages can't show:
We read public map data around Kern County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Kern County average
How we know this about Kern County
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at county grain; hard-freeze dates from NOAA 1991–2020 28°F normals at this county’s own record where one resolves, and the labelled statewide window where none does; soils from the USDA NRCS SSURGO survey, area-weighted across the county’s own map units; boundaries and acreage from US Census TIGER/Line 2025; the contamination and pesticide records from the federal sources named in their beats above. Where Kern County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Kern County
When does frost risk typically end in Kern County?
The last hard freeze (28°F) in Kern County typically lands around Jan 23, 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 13.
How long is the growing season in Kern County?
Measured between 28°F hard freezes, Kern County sees about 319 frost-free days — roughly Jan 23 through Dec 8, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 13 to Nov 24, about 284 days.
Is the soil safe to grow vegetables in Kern County?
The federal record around Kern County runs heavier than most — 8,118 documented sites, mostly Brownfields entries (4,706), the nearest Mining record about 0.9 miles out — so test the soil before planting food in the ground, and raised beds with clean imported soil grow well in the meantime. Even here, proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what's recorded and where.
Everything above is measured at Kern County's scale — its 9b band and its 319-day season. Your yard writes its own version of Kern County's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
Will It Grow Here?
Zone fit is the first question — each answer below reads California's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Kern County’s own scale
9 of the readings below were taken at Kern County's own scale — its own ~319-day span between 28°F freezes, the 3 most extensive soil series mapped here and 8,118 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Kern County's own USDA hardiness band, zones 9bUSDA PHZM 2023
- Kern County's own 28°F hard-freeze dates and its ~319-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Kern CountyUSDA NRCS SSURGO
- 8,118 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Mining record about 0.9 miles outFederal environmental registers
- Kern County's boundary and the 5,206,186 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9b and a ~319-day seasonGrowable Ground crop-matching engine
- The 4 ecoregions Kern County spans, Central California Valley the largestUS EPA Level III Ecoregions
- Open occurrence records documented in Kern County for a tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Kern County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every California grower plans around — written at state scale, so they stay on the state guidefrom California
What this page can’t tell you
- How the season shifts across Kern County — the ~319 days above is one reading at its centre; the 12 towns below each carry their owntowns in this county →
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Kern County's 5,206,186 acreswhy one lot differs from the next →
- Which of those 8,118 documented sites actually reaches your soil — that needs your address, the wind, and the groundwater directionhow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — none of it survives being averaged over Kern Countyread your own land →