Washoe County, in Nevada, sits in USDA hardiness zone 7a — a zone band wide enough that plant choice, not possibility, is the interesting question.
On paper, cabbage, blackberry, california poppy, and collard greens all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Washoe County lies within the Truckee Meadows / Reno — a regional growing area with its own character.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Washoe County holds more than one microclimate.
Soils and elevations shift across Washoe 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 Washoe County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Washoe County — the short answer
Washoe County, Nevada: USDA zone 7a, about 146 days between hard freezes, across 4.0M acres.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 20
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Oct 13
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~146
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 4.0M 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 7a is Washoe County's average, not your lot's — a low corner or a tree line moves it. Against Washoe County's 146-day season, see what your own ground reads.
One county, several growing seasons
Washoe County's hard-freeze record runs about 146 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: Spanish Springs at about 196 days (against the county's ~146).
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 ~146-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 in Washoe County
Across a year, Washoe County accumulates about 1,682 growing degree days above 50°F, about 461 fewer than the middle Nevada county — ahead of 3 of Nevada’s 17 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.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Washoe County
Across Washoe County, the ground is predominantly Mollisols, where Devada, Wylo, and Old camp are the most extensive named soil series. The soil is generally well drained with a very cobbly loam surface. Topsoil pH runs about 6.7–7.5, neutral. Rainfall drains through hydrologic group D soils.
Soil order
Mollisols
Drainage
Well drained
Hydric soils
1%
Soil still varies lot by lot — soil types explained.
How the ground varies across Washoe County
The USDA soil survey maps 82% of Washoe County as well drained — but another 14% drains differently: 6% somewhat excessively drained, 3% moderately well drained.
Devada is the most extensive named soil at 6% of mapped acres, then Wylo (3%) and Old camp (3%).
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 Washoe County
Each reading below is measured for Washoe 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 Washoe 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 Washoe County runs about pH 6.7–7.5, 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
MeasuredWashoe County 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
MeasuredWashoe County sits in USDA hardiness zone 7a.
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 Washoe County is in
Washoe County spans 2 EPA Level III ecoregions — Northern Basin and Range (50%) and Central Basin and Range (46%). 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 Washoe County
We scored all 1,086 plants against Washoe County's own USDA zone 7a and its own 146-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 Nevada profile.
Is it too late to plant in Washoe County?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Apr 22; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 20 (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. When the window is tight, the fall moves are quick ones — baby greens, radishes, and garlic set for next season.
Documented around Washoe County
- monarch butterfly62 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Washoe County
USGS estimates 4,452 lb of Glyphosate on Washoe County farmland in 2019, its largest by weight, ahead of Chlorpyrifos (1,107 lb) and 2,4-d (1,069 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 Washoe County — and how to grow with it.
We checked the federal record across Washoe County — 2,262 documented sites across 8 of the 9 source types we track.
The most significant on record: 12 Superfund sites (none NPL-listed). Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
Washoe 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 Washoe County
Closest first, across Washoe County. Listing isn't leaking, and distance isn't exposure.
- 021 N32 E21 09AAAD1Nitrate · 4.8 mi
- 021 N34 E22 29DBAD1Nitrate · 9.4 mi
- 021 N34 E22 18BBCA1 TOO KAPU TAWAKA FLOWINGNitrate · 9.6 mi
- 021 N32 E20 33DDDC1 Flw Well nr Buffalo SloughNitrate · 9.6 mi
- 021 N32 E20 32DADC1Nitrate · 9.8 mi
- 021 N33 E22 26CC 1Nitrate · 10.5 mi
- Copper King #1 ProspectMining · 11.1 mi
- Copper King ProspectMining · 11.1 mi
- Mountain View Tungsten ProspectMining · 11.2 mi
- Copper King # 1Mining · 11.3 mi
- Silver Bell MineMining · 11.3 mi
- Silver BellMining · 11.6 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Washoe 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 Washoe County.
Total Sites
2,262
across Washoe County
Risk Level
High
Highest-severity
12 Superfund sites (none NPL-listed)
Severity Distribution
across Washoe County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Washoe County, Mining runs higher than the national average — 165 sites across Washoe County. 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 Washoe 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 Washoe County average
Your land is one point inside Washoe County
Everything above resolves to Washoe County as a whole — one PHZM band and one county frost record, read across 4.0M 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 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 Washoe County Average
Washoe County Average
- ●USDA Zones 7a, averaged across Washoe County
- ●One soil character for all of Washoe County
- ●Frost dates read at Washoe County's scale: May 20 to Oct 13
YOUR Parcel
- ✓Your exact zone, not Washoe County's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Washoe County
Pull a site-specific report for your exact address in Washoe County, Nevada — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Washoe County averages can't show:
We read public map data around Washoe County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Washoe County average
How we know this about Washoe 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 Washoe County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Washoe County
When does frost risk typically end in Washoe County?
The last hard freeze (28°F) in Washoe County typically lands around May 20, 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 10.
How long is the growing season in Washoe County?
Measured between 28°F hard freezes, Washoe County sees about 146 frost-free days — roughly May 20 through Oct 13, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Jun 10 to Sep 29, about 111 days.
Is the soil safe to grow vegetables in Washoe County?
The federal record around Washoe County runs heavier than most — 2,262 documented sites, mostly Underground Storage Tanks entries (989), the nearest Nitrate record about 4.8 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 gardeners stretch the season in Washoe County?
With about 146 frost-free days between hard freezes, Washoe County 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 20 hard-freeze normal stretches the season without touching the calendar.
Everything above is measured at Washoe County's scale — its 7a band and its 146-day season. Your yard writes its own version of Washoe 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 Nevada's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Washoe County’s own scale
9 of the readings below were taken at Washoe County's own scale — its own ~146-day span between 28°F freezes, the 3 most extensive soil series mapped here and 2,262 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Washoe County's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Washoe County's own 28°F hard-freeze dates and its ~146-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Washoe CountyUSDA NRCS SSURGO
- 2,262 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Nitrate record about 4.8 miles outFederal environmental registers
- Washoe County's boundary and the 4,042,162 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~146-day seasonGrowable Ground crop-matching engine
- The 2 ecoregions Washoe County spans, Northern Basin and Range the largestUS EPA Level III Ecoregions
- Open occurrence records documented in Washoe County for a tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Washoe County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Nevada grower plans around — written at state scale, so they stay on the state guidefrom Nevada
What this page can’t tell you
- How the season shifts across Washoe County — the ~146 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 Washoe County's 4,042,162 acreswhy one lot differs from the next →
- Which of those 2,262 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 Washoe Countyread your own land →