Garden Valley, Idaho, 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.
Reliable performers under these conditions include cabbage, blackberry, california poppy, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Garden Valley, 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 Garden Valley 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 Garden Valley — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Garden Valley — the short answer
Garden Valley, Idaho: USDA zone 6b, about 171 days between hard freezes, across 5K acres of town.
- USDA zone
- 6b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 25
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 13
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~171
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 5K 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 Garden Valley's average, not your lot's — a low corner or a tree line moves it. Against Garden Valley's 171-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Garden Valley
Each reading below is measured for Garden Valley itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredGarden Valley runs about 171 days between hard freezes — a moderate growing season.
There is room for the full run of cool-season crops plus a warm-season main crop, but the calendar is tight enough that a late spring or early fall frost still decides how much finishes.
Time warm-season transplants to your last hard freeze, and a few weeks of season extension turns a near-miss harvest into a sure one.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredGarden Valley 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 Garden Valley is in
Garden Valley sits in the Idaho Batholith — EPA Level III, inside the wider Northwestern Forested Mountains. That is read at Garden Valley's own centroid rather than borrowed from Boise County.
What Grows in Garden Valley
Every plant below cleared Garden Valley's own zone 6b and its 171-day season. Each card opens that plant's Idaho profile. How we score.
Is it too late to plant in Garden Valley?
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 Mar 28; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 25 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 13 — long-season crops need about 90 days of runway, quick greens only 30. Even past midsummer there is room for a true fall garden here, and garlic planted near the close carries the momentum into next year.
What's on the federal record near Garden Valley
Closest first, within ~10 miles of Garden Valley. Listing isn't leaking, and distance isn't exposure.
- 09N 04E 26BDB1Nitrate · 2200 ft
- MARY E CONN - CROUCH LUMBUnderground Storage Tanks · 2300 ft
- GARDEN VALLEY CHEVRONUnderground Storage Tanks · 0.5 mi
- WEILMUNSTER PITToxics Release Inventory · 1.8 mi
- 09N 04E 15CCA1Nitrate · 2.0 mi
- H.G. ClaimsMining · 2.0 mi
- CROUCH MERCUnderground Storage Tanks · 2.2 mi
- PACKER JOHN MICROWAVEUnderground Storage Tanks · 2.3 mi
- GARDEN VALLEY WORK CENTERUnderground Storage Tanks · 2.3 mi
- SIX MILE PROJECT CAMPUnderground Storage Tanks · 2.3 mi
- 08N 05E 06DDC1Nitrate · 3.4 mi
- 09N 04E 03CDC1Nitrate · 3.6 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Garden Valley'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 Garden Valley.
Total Sites
100
within ~10 miles of Garden Valley
Risk Level
High
Highest-severity
1 Toxics Release Inventory facility
Sources Checked
within ~10 miles of Garden Valley
Severity Distribution
within ~10 miles of Garden Valley
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Garden Valley, Mining runs higher than the national average — 75 sites within ~10 miles of Garden Valley. That's not a problem with your land — it's information about it.
Mining: Mining sites — both historic and active — can leach heavy metals (arsenic, lead, cadmium, mercury) into soil and water for centuries after operations cease.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Check your specific parcel in Garden Valley
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 Garden Valley average
Your land is one point inside Garden Valley
Everything above resolves to Garden Valley as a whole — one PHZM band and one 28°F frost record, read across 5K 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 Garden Valley Average
Garden Valley Average
- ●USDA Zones 6b, averaged across Garden Valley
- ●One soil character for all of Garden Valley
- ●Frost dates read at Garden Valley's scale: Apr 25 to Oct 13
YOUR Parcel
- ✓Your exact zone, not Garden Valley's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Garden Valley
Pull a site-specific report for your exact address in Garden Valley, Idaho — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Garden Valley averages can't show:
We read public map data around Garden Valley — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Garden Valley average
How we know this about Garden Valley
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 Garden Valley’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 Garden Valley
When does frost risk typically end in Garden Valley?
The last hard freeze (28°F) in Garden Valley typically lands around Apr 25, 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 May 16.
When is the first frost in Garden Valley?
The first hard freeze (28°F) in Garden Valley typically arrives around Oct 13, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 29, so the watching starts about Sep 13 — about 171 days after the spring freeze cleared.
How long is the growing season in Garden Valley?
Measured between 28°F hard freezes, Garden Valley sees about 171 frost-free days — roughly Apr 25 through Oct 13, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 16 to Sep 29, about 136 days.
Is the soil safe to grow vegetables in Garden Valley?
The federal record around Garden Valley runs heavier than most — 100 documented sites, mostly Mining entries (75), the nearest Nitrate record about 0.4 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.
How do I protect my plants from frost in Garden Valley?
From about Sep 13 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 Oct 13 (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 Oct 13. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Garden Valley's scale — its 6b band and its 171-day season. Your yard writes its own version of Garden Valley'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 Garden Valley’s own scale
6 of the readings below were taken at Garden Valley's own scale — its own ~171-day season between 28°F freezes, the 4,689 acres it covers and 100 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Garden Valley's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Garden Valley's own 28°F hard-freeze dates, about Apr 25 and Oct 13 and the ~171-day span between themNOAA 1991–2020 Climate Normals
- 100 documented contamination sites on the federal record near Garden Valley, the closest Nitrate record about 0.4 miles out from the town centreFederal environmental registers
- Garden Valley's boundary and the 4,689 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~171-day seasonGrowable Ground crop-matching engine
- The ecoregion at Garden Valley's own centroid, the Idaho BatholithUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Garden Valley's 4,689 acres read through its county's SSURGO summaryfrom Boise County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Boise County
- The growing challenges every Idaho grower plans around — written at state scale, so they stay on the state guidefrom Idaho
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Boise County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Garden Valley's 4,689 acreswhy one lot differs from the next →
- Which side of Garden Valley you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 4,689 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record about 0.4 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 Garden Valley-wide figureread your own land →
More in Idaho
Growing region
Nearby growing guides