Calpine, California, sits in USDA hardiness zone 6b — 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 cabbage, blackberry, california poppy, and collard greens — though what thrives on any one site still turns on its specific soil, sun, and drainage.
Even in Calpine, 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 Calpine 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 Calpine — soil, climate, flood, and parcel records. How we handle your address.
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Calpine — the short answer
Calpine, California: USDA zone 6b, about 146 days between hard freezes, across 454 acres of town.
- USDA zone
- 6b
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 14
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 7
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~146
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 454 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 6b is Calpine's average, not your lot's — a low corner or a tree line moves it. Against Calpine's 146-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Calpine
Each reading below is measured for Calpine itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredCalpine runs about 146 days between hard freezes — a short growing season.
Long-maturing crops like melons, sweet potatoes, and winter squash can run out of runway before the first hard freeze, ripening late or not at all.
Lead with fast-maturing varieties, and stretch the season on both ends with cold frames, low tunnels, or a greenhouse.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredCalpine sits in USDA hardiness zone 6b.
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 Calpine is in
Calpine sits in the Sierra Nevada — EPA Level III, inside the wider Northwestern Forested Mountains. That is read at Calpine's own centroid rather than borrowed from Sierra County.
What Grows in Calpine
Every plant below cleared Calpine's own zone 6b and its 146-day season. Each card opens that plant's California profile. How we score.
Is it too late to plant in Calpine?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Apr 16; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 14 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 7 — long-season crops need about 90 days of runway, quick greens only 30. In a season this compact, fast finishers and cold-hardy greens do the late work, and garlic tucked in before the freeze repays you next summer.
What's on the federal record near Calpine
Closest first, within ~10 miles of Calpine. Listing isn't leaking, and distance isn't exposure.
- Antelope NeckMining · 5.3 mi
- WHITEHAWK RANCHBrownfields · 6.1 mi
- WHGC VENTURE LLC DBA WHITEHAWK RANCH GOLF CLUBBrownfields · 6.2 mi
- CALTRANS DISTRICT 03Brownfields · 6.4 mi
- TIM H BEALS DIRECTOR OF TRANSPORTATIONBrownfields · 6.4 mi
- Sierraville Service and Country StoreUnderground Storage Tanks · 6.5 mi
- PACIFIC BELLBrownfields · 6.6 mi
- ValentineMining · 7.5 mi
- LOYALTON TRANSFER STATIONBrownfields · 7.6 mi
- Big Mohawk MineMining · 7.6 mi
- Sierra HomestakeMining · 7.7 mi
- Copper MineMining · 7.9 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Calpine'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 Calpine.
Severity Distribution
within ~10 miles of Calpine
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Calpine, two things run higher than the national average within ~10 miles of Calpine — Mining (13 sites) and Brownfields (20 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Mining: Mining sites — both historic and active — can leach heavy metals (arsenic, lead, cadmium, mercury) into soil and water for centuries after operations cease.
Brownfields: Brownfield sites are former commercial or industrial properties where legacy soil contamination (heavy metals, PAHs, petroleum compounds) may persist.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Check EPA brownfield remediation status — many sites have completed cleanup with institutional controls.
Check your specific parcel in Calpine
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 Calpine average
Your land is one point inside Calpine
Everything above resolves to Calpine as a whole — one PHZM band and one 28°F frost record, read across 454 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 Calpine Average
Calpine Average
- ●USDA Zones 6b, averaged across Calpine
- ●One soil character for all of Calpine
- ●Frost dates read at Calpine's scale: May 14 to Oct 7
YOUR Parcel
- ✓Your exact zone, not Calpine's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Calpine
Pull a site-specific report for your exact address in Calpine, California — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Calpine averages can't show:
We read public map data around Calpine — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Calpine average
How we know this about Calpine
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 Calpine’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 Calpine
When does frost risk typically end in Calpine?
The last hard freeze (28°F) in Calpine typically lands around May 14, 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 Jun 4.
When is the first frost in Calpine?
The first hard freeze (28°F) in Calpine typically arrives around Oct 7, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 23, so the watching starts about Sep 7 — about 146 days after the spring freeze cleared.
How long is the growing season in Calpine?
Measured between 28°F hard freezes, Calpine sees about 146 frost-free days — roughly May 14 through Oct 7, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Jun 4 to Sep 23, about 111 days.
Is the soil safe to grow vegetables in Calpine?
The federal record around Calpine is light — 35 documented sites across the 9 federal source types we checked, mostly Brownfields entries (20), the nearest Mining record about 5.3 miles out — and proximity to a documented site is information, not a diagnosis of any one yard. Growing food here starts from a strong position; a soil test before new food beds settles any site-specific question.
How do gardeners stretch the season in Calpine?
With about 146 frost-free days between hard freezes, Calpine rewards the classic extension moves: floating row cover buys roughly two to four extra weeks at each shoulder — on this season that is a working window nearer 174 to 202 days — and cold frames or low tunnels buy more. Starting transplants indoors ahead of the May 14 hard-freeze normal stretches the season without touching the calendar.
Everything above is measured at Calpine's scale — its 6b band and its 146-day season. Your yard writes its own version of Calpine'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 Calpine’s own scale
6 of the readings below were taken at Calpine's own scale — its own ~146-day season between 28°F freezes, the 454 acres it covers and 35 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Calpine's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Calpine's own 28°F hard-freeze dates, about May 14 and Oct 7 and the ~146-day span between themNOAA 1991–2020 Climate Normals
- 35 documented contamination sites on the federal record near Calpine, the closest Mining record about 5.3 miles out from the town centreFederal environmental registers
- Calpine's boundary and the 454 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~146-day seasonGrowable Ground crop-matching engine
- The ecoregion at Calpine's own centroid, the Sierra NevadaUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Calpine's 454 acres read through its county's SSURGO summaryfrom Sierra County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Sierra 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 Sierra County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Calpine's 454 acreswhy one lot differs from the next →
- Which side of Calpine you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 454 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Mining record about 5.3 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 Calpine-wide figureread your own land →
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