Farson, Wyoming, sits in USDA hardiness zone 4a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
On paper, okra, cranberry, cilantro, and zucchini all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Even in Farson, 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 Farson 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 Farson — soil, climate, flood, and parcel records. How we handle your address.
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Farson — the short answer
Farson, Wyoming: USDA zone 4a, about 110 days between hard freezes, across 15K acres of town.
- USDA zone
- 4a
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 28
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Sep 15
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~110
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 15K 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 4a is Farson's average, not your lot's — a low corner or a tree line moves it. Against Farson's 110-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Farson
Each reading below is measured for Farson itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredFarson runs about 110 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
MeasuredFarson sits in USDA hardiness zone 4a.
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 Farson is in
Farson sits in the Wyoming Basin — EPA Level III, inside the wider North American Deserts. That is read at Farson's own centroid rather than borrowed from Sweetwater County.
What Grows in Farson
Every plant below cleared Farson's own zone 4a and its 110-day season. Each card opens that plant's Wyoming profile. How we score.
Is it too late to plant in Farson?
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 Apr 30; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 28 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Sep 15 — 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.
What's on the federal record near Farson
Closest first, within ~10 miles of Farson. Listing isn't leaking, and distance isn't exposure.
- 25-106-13cbb02Nitrate · 1.2 mi
- 25-106-13cbb01Nitrate · 1.2 mi
- Farson SchoolUnderground Storage Tanks · 2.0 mi
- QLB RMLR FarsonUnderground Storage Tanks · 2.0 mi
- QTM RMLR South PassUnderground Storage Tanks · 2.0 mi
- Radosevich LivestockUnderground Storage Tanks · 2.0 mi
- FARSON HIGH SCHOOLBrownfields · 2.0 mi
- JCB TRUCKINGBrownfields · 2.0 mi
- WYDOT FARSONBrownfields · 2.1 mi
- 26-106-35aa 01Nitrate · 2.5 mi
- 25-106-28aac01Nitrate · 3.0 mi
- WY DOT FarsonUnderground Storage Tanks · 3.0 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Farson'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 Farson.
Sources Checked
within ~10 miles of Farson
Severity Distribution
within ~10 miles of Farson
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Farson, Nitrate runs higher than the national average — 20 sites within ~10 miles of Farson. Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Farson
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 Farson average
Your land is one point inside Farson
Everything above resolves to Farson as a whole — one PHZM band and one 28°F frost record, read across 15K 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 Farson Average
Farson Average
- ●USDA Zones 4a, averaged across Farson
- ●One soil character for all of Farson
- ●Frost dates read at Farson's scale: May 28 to Sep 15
YOUR Parcel
- ✓Your exact zone, not Farson's 4a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Farson
Pull a site-specific report for your exact address in Farson, Wyoming — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Farson averages can't show:
We read public map data around Farson — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Farson average
How we know this about Farson
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 Farson’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 Farson
When does frost risk typically end in Farson?
The last hard freeze (28°F) in Farson typically lands around May 28, 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 18.
When is the first frost in Farson?
The first hard freeze (28°F) in Farson typically arrives around Sep 15, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 1, so the watching starts about Aug 16 — about 110 days after the spring freeze cleared.
How long is the growing season in Farson?
Measured between 28°F hard freezes, Farson sees about 110 frost-free days — roughly May 28 through Sep 15, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Jun 18 to Sep 1, about 75 days.
Is the soil safe to grow vegetables in Farson?
The federal record around Farson is light — 36 documented sites across the 9 federal source types we checked, mostly Nitrate entries (20), the nearest Nitrate record about 1.2 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 Farson?
With about 110 frost-free days between hard freezes, Farson 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 138 to 166 days — and cold frames or low tunnels buy more. Starting transplants indoors ahead of the May 28 hard-freeze normal stretches the season without touching the calendar.
Everything above is measured at Farson's scale — its 4a band and its 110-day season. Your yard writes its own version of Farson'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 Farson’s own scale
6 of the readings below were taken at Farson's own scale — its own ~110-day season between 28°F freezes, the 15,325 acres it covers and 36 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Farson's own USDA hardiness band, zones 4aUSDA PHZM 2023
- Farson's own 28°F hard-freeze dates, about May 28 and Sep 15 and the ~110-day span between themNOAA 1991–2020 Climate Normals
- 36 documented contamination sites on the federal record near Farson, the closest Nitrate record about 1.2 miles out from the town centreFederal environmental registers
- Farson's boundary and the 15,325 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4a and a ~110-day seasonGrowable Ground crop-matching engine
- The ecoregion at Farson's own centroid, the Wyoming BasinUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Farson's 15,325 acres read through its county's SSURGO summaryfrom Sweetwater County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Sweetwater County
- The growing challenges every Wyoming grower plans around — written at state scale, so they stay on the state guidefrom Wyoming
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Sweetwater County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Farson's 15,325 acreswhy one lot differs from the next →
- Which side of Farson you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 15,325 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record about 1.2 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 Farson-wide figureread your own land →
More in Wyoming
Wider growing context
What grows across WyomingFarson sits outside our named growing regions, so Wyoming as a whole is its closest context here.
Nearby growing guides