The Livermore Valley spans USDA hardiness zone 9b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
Livermore Valley isn't Napa or Sonoma with the coast filed off — it's an inland east-west trough in the East Bay hills (Alameda and Contra Costa counties) where afternoon marine air funnels in off San Francisco Bay through the Altamont gap, then drains back out overnight. That hands growers a wider day-to-night temperature swing than the cooler North Coast valleys, over gravelly, fast-draining alluvial soils that push vines toward concentration instead of vigor. It sits in USDA zone 9b with a long frost-free run of roughly 332-334 days, but the growing identity here is warm-climate: sun-and-wind Bordeaux whites and Rhône reds, not fog-belt Pinot. This is the home valley of California's Wente and Concannon plantings (both established 1883) and the widely propagated Wente Chardonnay clone. A recognized American Viticultural Area since 1982 (27 CFR §9.30), so its boundary is a real federal designation, not a marketing radius — and this page is scoped to Livermore's own two counties, giving frost and season numbers that are its own rather than a North Coast average. These conditions suit tomato, artichoke, fig, and california poppy — a starting list any specific site will trim or extend with its own soil, sun, and drainage.
The Livermore Valley spans California.
Your yard isn't all of the Livermore Valley.
The Livermore Valley spans USDA zones 9b, but your parcel sits in exactly one — and slope, tree cover, and low spots nudge it further. 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 Livermore Valley — soil, climate, flood, and parcel records. How we handle your address.
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The Livermore Valley — the short answer
The Livermore Valley: USDA zones 9b, 332–334 frost-free days, in California.
- USDA zones
- 9b
- USDA PHZM 2023, aggregated over the footprint
- Frost-free season
- 332–334 days
- NOAA Regional Climate Centers ACIS, 1991-2020
- Counties
- 2
- US Census TIGER/Line 2025
- Region type
- County cluster
- Growable Ground growing-region registry
Region boundary: Growable Ground growing-region registry — curated county clusters, EPA Level III ecoregions, and town clusters drawn finer than any county. Where a region publishes no measured season, no season figure is shown.
Hardiness Zone Range
What Grows in the Livermore Valley
Plants matched to the Livermore Valley's USDA zones 9b, ordered by how much hardiness margin each has across the region — the ones with room to spare at both ends of this band lead. Each links to its full growing profile.
Native Plants of the Livermore Valley
Plants the USDA PLANTS Database documents as native and present in this region’s state, kept only where the published hardiness range meets the Livermore Valley’s USDA zones 9b — closest range match first. Presence is recorded by state, so a plant can be documented across the state and still be scarce in your corner of the region.
The ground across the Livermore Valley
The USDA soil survey maps this ground county by county. These are those records weighted by land area across two member counties — this region’s own profile, not a state figure.
The ground is predominantly Mollisols, at 30% of mapped acres, followed by Vertisols (24%), Alfisols (22%) and Entisols (11%). Six soil orders appear somewhere inside the footprint, which is the honest reason a regional soil answer only goes so far. The most extensive named soils are Los Osos, Altamont, and Millsholm.
54% of those acres are well drained, and another 8% poorly drained, 7% somewhat excessively drained. Topsoil pH runs 6.1–7.3 between the lowest and the highest county on record.
Soil order
Mollisols
Drainage
Well drained
Topsoil pH
6.1–7.3
Hydric soils
14%
Soil changes across a driveway, so which of these your own ground sits on is a parcel question rather than a regional one. Alameda County holds the most wetland ground here, at 14% — soil types explained.
USDA NRCS SSURGO via Soil Data Access
What this means for growing in the Livermore Valley
The soil survey reads this ground county by county, and the readings above are those records summed across the Livermore Valley. Here is what they mean for a garden here — and the move an experienced grower makes about each one.
Drainage
From county records54% of the mapped acres across the Livermore Valley are well drained — ground that drains quickly. That is area-weighted across all two of its mapped counties.
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
From county recordsTopsoil across the Livermore Valley runs pH 6.1–7.3 — near neutral in all two of them.
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
Safe to Grow Here?
What the federal record shows across the Livermore Valley — and how to grow with it.
Across the Livermore Valley's 2 counties the federal record holds 17,205 documented sites, mostly Brownfields (15,016), Underground Storage Tanks (931) and Nitrate (632). The heaviest single county is Alameda County, with 11,350.
That is a regional count, not a reading of any one lot — proximity to a documented site is information, not a diagnosis. Open the map outlined to the Livermore Valley to see which records sit where you actually grow.
Sources Checked
Summed across the 2 counties in the Livermore Valley
A note from Gnorman
What an experienced grower watches for around here
In and around the Livermore Valley, Brownfields runs higher than the national average — 15,016 sites across the 2 counties in the Livermore Valley. 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.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
Your land is one point inside the Livermore Valley
Everything above resolves to the Livermore Valley as a whole — a footprint spanning USDA zones 9b. Your parcel sits in exactly one of them. 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 region 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 regional average.
Your Lot vs the Livermore Valley Average
Livermore Valley Average
- ●USDA Zones 9b, averaged across Livermore Valley
- ●One soil character for all of Livermore Valley
- ●State-average frost dates
YOUR Parcel
- ✓Your exact zone, not Livermore Valley's 9b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in the Livermore Valley
Pull a site-specific report for your exact address in the Livermore Valley — soil, sun, drainage, frost risk, contamination, and scored plant recommendations.
Three things about your lot that Livermore Valley averages can't show:
We read public map data around The Livermore Valley — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Livermore Valley average
How we know this about the Livermore Valley
The boundary: a cluster of neighboring counties. Growing regions have no official boundary, so this footprint is our published one, and every figure on this page was measured over the counties inside it rather than borrowed from the state around it.
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, aggregated across the footprint; the growing season from NOAA Regional Climate Centers ACIS 1991–2020 28°F normals, read at each member’s own record; boundaries from US Census TIGER/Line 2025; the contamination record from the federal sources named in that beat above; the soil from the USDA NRCS SSURGO survey, read at each member county’s own record and weighted to this footprint by land area. Where a member carries no record of its own, it is absent from the figure rather than filled in.
Common questions about the Livermore Valley
What hardiness zone is the Livermore Valley?
The Livermore Valley spans USDA hardiness zones 9b, aggregated from the USDA Agricultural Research Service Plant Hardiness Zone Map 2023 across the region's counties. Zones reflect average annual extreme minimum temperatures from 1991–2020 data.
How long is the growing season in the Livermore Valley?
Measured between 28°F hard freezes, the Livermore Valley's counties mostly run 333 to 334 frost-free days, median 333 (NOAA Regional Climate Centers ACIS, 1991–2020, over 2 member counties). That 1-day spread is the honest read — no single season describes 2 counties, and each county guide below carries its own.
When does frost risk end in the Livermore Valley?
Across the Livermore Valley, the middle half of member counties see their last 28°F hard freeze between Jan 13 and Jan 15 (median Jan 14), and their first fall freeze between Dec 13 and Dec 14. Those are hard freezes, not the last light frost: tender transplants wait for about Feb 4, and elevation decides which end of a 2-day spread you garden in.
What grows well in the Livermore Valley?
The Livermore Valley's conditions suit plants such as Tomato, Artichoke, Fig, California Poppy, Rosemary, Olive. What actually thrives on any one site still turns on its specific soil, sun, and drainage — we score each plant against the real conditions at your address.
How is the Livermore Valley defined?
The Livermore Valley is defined here as a curated cluster of 2 neighboring counties that share a growing character. Growing regions have no official boundary, so this footprint is our published one — every county in it is named on this page.
Which states does the Livermore Valley cover?
The Livermore Valley spans California. Each state's full growing guide is linked on this page.
What other growing regions cover the same states?
Pacific Northwest, California Central Valley, Sacramento Valley, San Joaquin Valley, Sierra Nevada Foothills, and Sonoran Desert share at least one state with the Livermore Valley. Growing regions overlap and interlock — a single address can sit inside more than one, which is why the precise read is always the parcel, not the region.
What this page reads at the Livermore Valley’s own scale
6 of the readings below were taken at the Livermore Valley's own scale — the zone 9b band across its footprint, a median 333-day season across its 2 counties and 17,205 documented federal contamination records across its 2 counties, 11,350 of them in Alameda County alone; one is borrowed from a wider read, named and linked below.
Measured here
- The USDA hardiness band 9b aggregated across all 2 counties in the footprintUSDA PHZM 2023
- The boundary itself — the 2 counties this region is curated fromGrowable Ground subregion registry
- The growing character that makes this region distinct from the states it crossesGrowable Ground subregion registry
- The 28°F season across the footprint — the middle half of its 2 counties run 333 to 334 frost-free days, median 333NOAA Regional Climate Centers ACIS, 1991-2020
- The federal contamination record over the whole footprint — 17,205 documented federal contamination records across its 2 counties, 11,350 of them in Alameda County aloneEPA, USGS and USDA federal site records
- The soil order mix across the footprint — 30% Mollisols, topsoil pH 6.1–7.3, area-weighted across its 2 mapped countiesUSDA NRCS SSURGO
Inherited from a wider read
- The candidate plant list — its state's curated sets, merged and filtered to zones 9bfrom California
What this page can’t tell you
- Which end of the 1-day range your ground sits at — 333 days at one extreme, 334 at the other, decided mostly by elevationfrost dates explained →
- Which of those soils your own ground sits on — the survey maps them county-wide, and they change across a drivewaysoil types explained →
- The soil pH, drainage, sun hours, and frost pockets on one specific lotwhy one lot differs from the next →
Explore the Livermore Valley
State growing guides
Counties in this region
Other growing regions across California
The maritime Northwest west of the Cascade crest — mild, wet winters and dry summers behind berries, tree fruit, and lush cool-season gardens. (Union of the west-side ecoregions.)
A vast flat alluvial trough with hot dry summers and rich soils — one of the most productive agricultural regions on earth, from almonds and stone fruit to row crops.
The cooler, wetter northern half of the Central Valley — rice, walnuts, tomatoes, and orchard fruit on rich alluvial bottomland.
The hot southern half of California's Central Valley — deep soils and intense sun behind almonds, stone fruit, grapes, and row crops at vast scale.
California's Gold Country foothills — rocky, well-drained slopes and warm days that suit wine grapes, olives, and Mediterranean orchard crops.
A warm desert of saguaro and palo verde with mild winters that allow desert citrus, dates, and prickly pear alongside intensive irrigated gardening.