Whitewater, Montana, sits in USDA hardiness zone 3b — a zone band wide enough that plant choice, not possibility, is the interesting question.
Crops well matched to these conditions include cabbage, cranberry, epazote, and collard greens — though what thrives on any one site still turns on its specific soil, sun, and drainage.
Even in Whitewater, 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 Whitewater 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 Whitewater — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Whitewater — the short answer
Whitewater, Montana: USDA zone 3b, about 145 days between hard freezes, across 679 acres of town.
- USDA zone
- 3b
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 7
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Sep 29
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~145
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 679 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 3b is Whitewater's average, not your lot's — a low corner or a tree line moves it. Against Whitewater's 145-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Whitewater
Each reading below is measured for Whitewater itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredWhitewater runs about 145 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
MeasuredWhitewater sits in USDA hardiness zone 3b.
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 Whitewater is in
Whitewater sits in the Northwestern Glaciated Plains — EPA Level III, inside the wider Great Plains. That is read at Whitewater's own centroid rather than borrowed from Phillips County.
What Grows in Whitewater
Every plant below cleared Whitewater's own zone 3b and its 145-day season. Each card opens that plant's Montana profile. How we score.
Is it too late to plant in Whitewater?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Apr 9; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 7 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Sep 29 — 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 Whitewater
Closest first, within ~10 miles of Whitewater. Listing isn't leaking, and distance isn't exposure.
- 35N31E26D 01Nitrate · 950 ft
- WHITEWATER SCHOOL DIST 20 AA&DUnderground Storage Tanks · 1400 ft
- BN WHITEWATER DEPOTUnderground Storage Tanks · 1400 ft
- 34N31E09DAAA01Nitrate · 3.5 mi
- OLSEN GRAIN & LIVESTOCKUnderground Storage Tanks · 5.6 mi
- FARM SUPPLY HARDWAREUnderground Storage Tanks · 6.5 mi
- K N ENERGY INC WHITEWATERUnderground Storage Tanks · 6.5 mi
- 36N32E26CDDB01Nitrate · 7.6 mi
- 35N33E19DBA 01Nitrate · 8.1 mi
Measured from Whitewater'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 Whitewater.
Severity Distribution
within ~10 miles of Whitewater
Highest-Severity Sites
Know Before You Grow
- •On a private well, test for nitrates: above 10 mg/L the water needs treatment before irrigating.
- •Underground tanks leak petroleum as they age — near a former filling station, test the soil.
Check your specific parcel in Whitewater
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 Whitewater average
Your land is one point inside Whitewater
Everything above resolves to Whitewater as a whole — one PHZM band and one 28°F frost record, read across 679 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 Whitewater Average
Whitewater Average
- ●USDA Zones 3b, averaged across Whitewater
- ●One soil character for all of Whitewater
- ●Frost dates read at Whitewater's scale: May 7 to Sep 29
YOUR Parcel
- ✓Your exact zone, not Whitewater's 3b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Whitewater
Pull a site-specific report for your exact address in Whitewater, Montana — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Whitewater averages can't show:
We read public map data around Whitewater — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Whitewater average
How we know this about Whitewater
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 Whitewater’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 Whitewater
When does frost risk typically end in Whitewater?
The last hard freeze (28°F) in Whitewater typically lands around May 7, 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 28.
When is the first frost in Whitewater?
The first hard freeze (28°F) in Whitewater typically arrives around Sep 29, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 15, so the watching starts about Aug 30 — about 145 days after the spring freeze cleared.
How long is the growing season in Whitewater?
Measured between 28°F hard freezes, Whitewater sees about 145 frost-free days — roughly May 7 through Sep 29, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 28 to Sep 15, about 110 days.
Is the soil safe to grow vegetables in Whitewater?
The federal record around Whitewater is light — 13 documented sites across the 9 federal source types we checked, mostly Nitrate entries (8), the nearest Nitrate record about 0.2 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 Whitewater?
With about 145 frost-free days between hard freezes, Whitewater 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 173 to 201 days — and cold frames or low tunnels buy more. Starting transplants indoors ahead of the May 7 hard-freeze normal stretches the season without touching the calendar.
Everything above is measured at Whitewater's scale — its 3b band and its 145-day season. Your yard writes its own version of Whitewater'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 Whitewater’s own scale
6 of the readings below were taken at Whitewater's own scale — its own ~145-day season between 28°F freezes, the 679 acres it covers and 13 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Whitewater's own USDA hardiness band, zones 3bUSDA PHZM 2023
- Whitewater's own 28°F hard-freeze dates, about May 7 and Sep 29 and the ~145-day span between themNOAA 1991–2020 Climate Normals
- 13 documented contamination sites on the federal record near Whitewater, the closest Nitrate record about 0.2 miles out from the town centreFederal environmental registers
- Whitewater's boundary and the 679 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 3b and a ~145-day seasonGrowable Ground crop-matching engine
- The ecoregion at Whitewater's own centroid, the Northwestern Glaciated PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Whitewater's 679 acres read through its county's SSURGO summaryfrom Phillips County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Phillips County
- The growing challenges every Montana grower plans around — written at state scale, so they stay on the state guidefrom Montana
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Phillips County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Whitewater's 679 acreswhy one lot differs from the next →
- Which side of Whitewater you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 679 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record about 0.2 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 Whitewater-wide figureread your own land →
More in Montana
Growing region
Nearby growing guides