Wilton, California, sits in USDA hardiness zone 9b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Among the crops suited to this profile: okra, meyer lemon, california poppy, and artichoke. The site-level story — soil, sun, drainage — decides the rest.
Even in Wilton, 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 Wilton 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 Wilton — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Wilton — the short answer
Wilton, California: USDA zone 9b, about 324 days between hard freezes, across 19K acres of town.
- USDA zone
- 9b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Jan 22
- Sacramento County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 12
- Sacramento County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~324
- Sacramento County normal — NOAA 1991–2020, nearest to this town
- Town 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 Sacramento County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9b is Wilton's average, not your lot's — a low corner or a tree line moves it. Against Wilton's 324-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Wilton
Each reading below is measured for Wilton itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsWilton runs about 324 days between hard freezes (read from Sacramento County, the closest normal to Wilton) — 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
MeasuredWilton 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 Wilton is in
Wilton sits in the Central California Valley — EPA Level III, inside the wider Mediterranean California. That is read at Wilton's own centroid rather than borrowed from Sacramento County.
What Grows in Wilton
Every plant below cleared Wilton's own zone 9b and its 324-day season. Each card opens that plant's California profile. How we score.
Is it too late to plant in Wilton?
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 22 (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 Wilton
Closest first, within ~10 miles of Wilton. Listing isn't leaking, and distance isn't exposure.
- 007N007E33Q001MNitrate · 800 ft
- 007N007E33G001MNitrate · 2400 ft
- MOBILE REPAIR & INSPECTION INCBrownfields · 0.8 mi
- LRBC CLEANUP INCBrownfields · 1.0 mi
- THE TOELLE FARM/BRUCE TOELLEBrownfields · 1.2 mi
- JOE THORNTON LOGGINGBrownfields · 1.5 mi
- K & M HARRIS INCBrownfields · 1.7 mi
- KERMIT JACOBSENBrownfields · 1.9 mi
- MIKE RAZZANO FARMBrownfields · 1.9 mi
- PDH TRUCKINGBrownfields · 2.2 mi
- KEN GUYBrownfields · 2.5 mi
- LAGUNA DEL SOL INCBrownfields · 2.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Wilton'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 Wilton.
Total Sites
508
within ~10 miles of Wilton
Risk Level
Elevated
Highest-severity
5 Toxics Release Inventory facilities
Sources Checked
within ~10 miles of Wilton
Severity Distribution
within ~10 miles of Wilton
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Wilton, two things run higher than the national average within ~10 miles of Wilton — Brownfields (406 sites) and PFAS (5 sites). 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.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Check EPA brownfield remediation status — many sites have completed cleanup with institutional controls.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check your specific parcel in Wilton
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 Wilton average
Your land is one point inside Wilton
Everything above resolves to Wilton as a whole — one PHZM band, read across 19K acres, with hard-freeze dates borrowed from Sacramento 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 Wilton Average
Wilton Average
- ●USDA Zones 9b, averaged across Wilton
- ●One soil character for all of Wilton
- ●Frost dates read at Wilton's scale: Jan 22 to Dec 12
YOUR Parcel
- ✓Your exact zone, not Wilton's 9b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Wilton
Pull a site-specific report for your exact address in Wilton, California — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Wilton averages can't show:
We read public map data around Wilton — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Wilton average
How we know this about Wilton
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 Sacramento 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 Wilton
When does frost risk typically end in Wilton?
The last hard freeze (28°F) in Wilton typically lands around Jan 22, 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 12.
When is the first frost in Wilton?
The first hard freeze (28°F) in Wilton 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 324 days after the spring freeze cleared.
How long is the growing season in Wilton?
Measured between 28°F hard freezes, Wilton sees about 324 frost-free days — roughly Jan 22 through Dec 12, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 12 to Nov 28, about 289 days.
Is the soil safe to grow vegetables in Wilton?
The federal record around Wilton is a meaningful one — 508 documented sites, mostly Brownfields entries (406), the nearest Nitrate 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 Wilton?
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 Wilton's scale — its 9b band and its 324-day season. Your yard writes its own version of Wilton'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 Wilton’s own scale
5 of the readings below were taken at Wilton's own scale — the 18,561 acres it covers and 508 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Wilton's own USDA hardiness band, zones 9bUSDA PHZM 2023
- 508 documented contamination sites on the federal record near Wilton, the closest Nitrate record about 0.2 miles out from the town centreFederal environmental registers
- Wilton's boundary and the 18,561 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9b and a ~324-day seasonGrowable Ground crop-matching engine
- The ecoregion at Wilton's own centroid, the Central California ValleyUS EPA Level III Ecoregions
Inherited from a wider read
- The 28°F hard-freeze dates — Wilton has no normal of its own, so its county's is the closest measured readfrom Sacramento County
- Soil character — no town-scale survey exists, so Wilton's 18,561 acres read through its county's SSURGO summaryfrom Sacramento County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Sacramento 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 Sacramento County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Wilton's 18,561 acreswhy one lot differs from the next →
- Which side of Wilton you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 18,561 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate 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 Wilton-wide figureread your own land →
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