Washington County, in Nebraska, sits in USDA hardiness zone 5b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Expect cabbage, cranberry, lavender, and collard greens to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Washington County holds more than one microclimate.
Soils and elevations shift across Washington 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 Washington County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Washington County — the short answer
Washington County, Nebraska: USDA zone 5b, about 204 days between hard freezes, across 250K acres.
- USDA zone
- 5b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 5
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Oct 26
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~204
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 250K 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 5b is Washington County's average, not your lot's — a low corner or a tree line moves it. Against Washington County's 204-day season, see what your own ground reads.
Heat in Washington County
Across a year, Washington County accumulates about 3,101 growing degree days above 50°F, about 261 more than the middle Nebraska county — ahead of 68 of Nebraska’s 93 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 Washington County
Across Washington County, the ground is predominantly Mollisols, where Marshall, Pohocco, and Nora are the most extensive named soil series. The soil is generally well drained with a silty clay loam surface. Topsoil pH runs about 6.1–7.2, neutral. Rainfall drains through hydrologic group C soils.
Soil order
Mollisols
Drainage
Well drained
Prime farmland
42%
Hydric soils
8%
Soil still varies lot by lot — soil types explained.
How the ground varies across Washington County
The USDA soil survey maps 75% of Washington County as well drained — but another 23% drains differently: 11% moderately well drained, 8% poorly drained.
Marshall is the most extensive named soil at 12% of mapped acres, then Pohocco (12%) and Nora (10%).
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 Washington County
Each reading below is measured for Washington 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 Washington County are well drained, in hydrologic group C — 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 Washington County runs about pH 6.1–7.2, 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
MeasuredWashington County runs about 204 days between hard freezes — a long growing season.
There is slack for succession plantings and slow-finishing crops: many vegetables can be sown twice, and the heat-lovers have time to ripen fully.
Plan a second sowing of quick crops after the first comes out, and use the fall window most gardeners let sit idle.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredWashington County sits in USDA hardiness zone 5b.
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 Washington County is in
Washington County sits in the Western Corn Belt Plains — EPA Level III, inside the wider Great Plains. One consistent ecological setting across the whole county.
What Grows in Washington County
We scored all 1,086 plants against Washington County's own USDA zone 5b and its own 204-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 Nebraska profile.
Is it too late to plant in Washington County?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 8; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 5 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 26 — long-season crops need about 90 days of runway, quick greens only 30. With a season this long, “too late” mostly means “switch crops” — second sowings and a full fall garden are the norm, with garlic closing the year.
Documented around Washington County
- monarch butterfly135 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Washington County
USGS estimates 168,842 lb of Glyphosate on Washington County farmland in 2019, its largest by weight, ahead of Atrazine (71,680 lb) and Metolachlor & Metolachlor-s (58,304 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 Washington County — and how to grow with it.
We checked the federal record across Washington County — 186 documented sites across 6 of the 9 source types we track.
The most significant on record: 8 Toxics Release Inventory facilities. Active industrial facilities reporting chemical releases to air, water, and land.
The federal record across Washington County is a modest one — a typical footprint for a growing area. Nothing here calls for alarm; it's worth knowing which recorded sites sit closest to where you grow, and each one on the map carries its type and location. If one turns out to be a near neighbor, a one-time soil test settles the question.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Washington County
Closest first, across Washington County. Listing isn't leaking, and distance isn't exposure.
- 18N 11E 10DC (U-147)Nitrate · 2.5 mi
- 18N 11E 4BB (U-149)Nitrate · 2.8 mi
- BLAIR, CITY OFPFAS · 2.9 mi
- TOEBBEN FEEDLOTCAFO · 3.2 mi
- WASHINGTON COUNTY ROAD DEPTBrownfields · 3.9 mi
- SPEEDEE MART 2707 BLAIRUnderground Storage Tanks · 4.2 mi
- SID DILLON CHEV OLDS PONT GEOBrownfields · 4.2 mi
- CASEYS GENERAL STORE #3344Underground Storage Tanks · 4.2 mi
- WOODHOUSE FORDBrownfields · 4.3 mi
- MUTUAL OF OMAHAUnderground Storage Tanks · 4.3 mi
- WALMART SUPERCENTER #4568Brownfields · 4.3 mi
- BLAIR AMOCOUnderground Storage Tanks · 4.3 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Washington 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 Washington County.
Total Sites
186
across Washington County
Risk Level
Moderate
Highest-severity
8 Toxics Release Inventory facilities
Sources Checked
across Washington County
Severity Distribution
across Washington County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Washington County, two things run higher than the national average across Washington County — Nitrate (124 sites) and CAFO (4 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
CAFO: CAFOs pose a different contamination profile than chemical sources.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Check your specific parcel in Washington 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 Washington County average
Your land is one point inside Washington County
Everything above resolves to Washington County as a whole — one PHZM band and one county frost record, read across 250K 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 Washington County Average
Washington County Average
- ●USDA Zones 5b, averaged across Washington County
- ●One soil character for all of Washington County
- ●Frost dates read at Washington County's scale: Apr 5 to Oct 26
YOUR Parcel
- ✓Your exact zone, not Washington County's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Washington County
Pull a site-specific report for your exact address in Washington County, Nebraska — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Washington County averages can't show:
We read public map data around Washington County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Washington County average
How we know this about Washington 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 Washington County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Washington County
When does frost risk typically end in Washington County?
The last hard freeze (28°F) in Washington County typically lands around Apr 5, 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 Apr 26.
How long is the growing season in Washington County?
Measured between 28°F hard freezes, Washington County sees about 204 frost-free days — roughly Apr 5 through Oct 26, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 26 to Oct 12, about 169 days.
Is the soil safe to grow vegetables in Washington County?
The federal record around Washington County shows 186 documented sites, mostly Nitrate entries (124), the nearest Nitrate record about 2.5 miles out — a typical footprint for a growing area, and proximity to a documented site is information, not a diagnosis of any one yard. It's worth seeing which recorded sites sit closest to where you grow, and testing the soil before new food beds near any of them.
Everything above is measured at Washington County's scale — its 5b band and its 204-day season. Your yard writes its own version of Washington 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 Nebraska's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Washington County’s own scale
9 of the readings below were taken at Washington County's own scale — its own ~204-day span between 28°F freezes, the 3 most extensive soil series mapped here and 186 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Washington County's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Washington County's own 28°F hard-freeze dates and its ~204-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Washington CountyUSDA NRCS SSURGO
- 186 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Nitrate record about 2.5 miles outFederal environmental registers
- Washington County's boundary and the 249,555 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~204-day seasonGrowable Ground crop-matching engine
- Washington County sitting wholly inside the Western Corn Belt PlainsUS EPA Level III Ecoregions
- Open occurrence records documented in Washington County for a tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Washington County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Nebraska grower plans around — written at state scale, so they stay on the state guidefrom Nebraska
What this page can’t tell you
- How the season shifts across Washington County — the ~204 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 Washington County's 249,555 acreswhy one lot differs from the next →
- Which of those 186 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 Washington Countyread your own land →