Seward 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.
A short list that earns its place here — cabbage, cranberry, lavender, and collard greens — with any one site's soil, sun, and drainage making the final cut.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Seward County holds more than one microclimate.
Soils and elevations shift across Seward 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 Seward County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Seward County — the short answer
Seward County, Nebraska: USDA zone 5b, about 193 days between hard freezes, across 366K acres.
- USDA zone
- 5b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 10
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Oct 20
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~193
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 366K 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 Seward County's average, not your lot's — a low corner or a tree line moves it. Against Seward County's 193-day season, see what your own ground reads.
Heat in Seward County
Across a year, Seward County accumulates about 3,173 growing degree days above 50°F, about 333 more than the middle Nebraska county — ahead of 76 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 Seward County
Across Seward County, the ground is predominantly Mollisols, where Hastings, Hobbs, and Muir are the most extensive named soil series. The soil is generally well drained with a silt loam surface. Topsoil pH runs about 5.8–6.2, moderately acidic. Rainfall drains through hydrologic group C soils.
Soil order
Mollisols
Drainage
Well drained
Prime farmland
53%
Hydric soils
6%
Soil still varies lot by lot — soil types explained.
How the ground varies across Seward County
The USDA soil survey maps 80% of Seward County as well drained — but another 19% drains differently: 12% somewhat poorly drained, 7% moderately well drained.
Hastings is the most extensive named soil at 27% of mapped acres, then Hobbs (8%) and Muir (8%).
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 Seward County
Each reading below is measured for Seward 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 Seward 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 Seward County runs about pH 5.8–6.2, 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
MeasuredSeward County runs about 193 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
MeasuredSeward 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 Seward County is in
Seward County spans 2 EPA Level III ecoregions — Central Great Plains (77%) and Western Corn Belt Plains (23%). 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 Seward County
We scored all 1,086 plants against Seward County's own USDA zone 5b and its own 193-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 Seward County?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 13; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 10 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 20 — long-season crops need about 90 days of runway, quick greens only 30. As the window narrows, the plantings just get faster — fall brassicas, then greens, then garlic to finish.
Documented around Seward County
- monarch butterfly1 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Seward County
USGS estimates 273,398 lb of Glyphosate on Seward County farmland in 2019, its largest by weight, ahead of Atrazine (131,009 lb) and Metolachlor & Metolachlor-s (102,704 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 Seward County — and how to grow with it.
We checked the federal record across Seward County — 92 documented sites across 7 of the 9 source types we track.
The most significant on record: 2 Superfund sites (none NPL-listed). Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
There's a meaningful federal record across Seward County — worth a look before you plant food, not a reason to hold back from growing. Proximity to a documented site is information, not a diagnosis of any one yard. A soil test before new food beds is the sensible precaution here, and the map shows exactly which sites sit where, so you can see what's actually near you.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Seward County
Closest first, across Seward County. Listing isn't leaking, and distance isn't exposure.
- BRIGGS CATTLE COMPANY DBA BRIGGS FEED YARDCAFO · 1.2 mi
- BRIGGS FEEDYARDCAFO · 1.2 mi
- 11N 2E26ADCC3 FP1-123Nitrate · 1.9 mi
- 11N 2E26ADCC1 FP1-90Nitrate · 1.9 mi
- 11N 2E26ADCC2 FP1-105Nitrate · 1.9 mi
- LONGVIEW FIBRE COMPANYBrownfields · 2.0 mi
- WALMART SUPERCENTER #885Brownfields · 2.1 mi
- WINFIELD SOLUTIONS, LLC - SEWARDBrownfields · 2.1 mi
- 11N 2E34AADA1Nitrate · 2.1 mi
- O'REILLY AUTO PARTS STORE 2100Brownfields · 2.1 mi
- CASEYS GENERAL STORE #2730Underground Storage Tanks · 2.2 mi
- 11N 2E26CCBB3 FP3-125Nitrate · 2.3 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Seward 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 Seward County.
Total Sites
92
across Seward County
Risk Level
Elevated
Highest-severity
2 Superfund sites (none NPL-listed)
Sources Checked
across Seward County
Severity Distribution
across Seward County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Seward County, two things run higher than the national average across Seward County — CAFO (10 sites) and Nitrate (30 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
CAFO: CAFOs pose a different contamination profile than chemical sources.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Seward 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 Seward County average
Your land is one point inside Seward County
Everything above resolves to Seward County as a whole — one PHZM band and one county frost record, read across 366K 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 Seward County Average
Seward County Average
- ●USDA Zones 5b, averaged across Seward County
- ●One soil character for all of Seward County
- ●Frost dates read at Seward County's scale: Apr 10 to Oct 20
YOUR Parcel
- ✓Your exact zone, not Seward County's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Seward County
Pull a site-specific report for your exact address in Seward County, Nebraska — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Seward County averages can't show:
We read public map data around Seward County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Seward County average
How we know this about Seward 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 Seward County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Seward County
When does frost risk typically end in Seward County?
The last hard freeze (28°F) in Seward County typically lands around Apr 10, 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 1.
How long is the growing season in Seward County?
Measured between 28°F hard freezes, Seward County sees about 193 frost-free days — roughly Apr 10 through Oct 20, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 1 to Oct 6, about 158 days.
Is the soil safe to grow vegetables in Seward County?
The federal record around Seward County is a meaningful one — 92 documented sites, mostly Nitrate entries (30), the nearest CAFO record about 1.2 miles out — so a soil test before new food beds is a sensible precaution here, not a reason to hold back from growing. Remember that proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what sits where.
Everything above is measured at Seward County's scale — its 5b band and its 193-day season. Your yard writes its own version of Seward 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 Seward County’s own scale
9 of the readings below were taken at Seward County's own scale — its own ~193-day span between 28°F freezes, the 3 most extensive soil series mapped here and 92 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Seward County's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Seward County's own 28°F hard-freeze dates and its ~193-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Seward CountyUSDA NRCS SSURGO
- 92 documented contamination sites inside the county boundary, distance-sorted from its center — the closest CAFO record about 1.2 miles outFederal environmental registers
- Seward County's boundary and the 365,715 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~193-day seasonGrowable Ground crop-matching engine
- The 2 ecoregions Seward County spans, Central Great Plains the largestUS EPA Level III Ecoregions
- Open occurrence records documented in Seward County for a tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Seward 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 Seward County — the ~193 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 Seward County's 365,715 acreswhy one lot differs from the next →
- Which of those 92 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 Seward Countyread your own land →