Union Valley, Texas, sits in USDA hardiness zone 8b — a zone band wide enough that plant choice, not possibility, is the interesting question.
A short list that earns its place here — cabbage, fig, california poppy, and collard greens — with any one site's soil, sun, and drainage making the final cut.
Even in Union Valley, 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 Union Valley 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 Union Valley — soil, climate, flood, and parcel records. How we handle your address.
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Union Valley — the short answer
Union Valley, Texas: USDA zone 8b, about 277 days between hard freezes, across 2K acres of city.
- USDA zone
- 8b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 23
- Hunt County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Nov 27
- Hunt County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~277
- Hunt County normal — NOAA 1991–2020, nearest to this town
- City area
- 2K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. No 30-year normal resolves at this town’s own centroid, so the hard-freeze dates are Hunt County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 8b is Union Valley's average, not your lot's — a low corner or a tree line moves it. Against Union Valley's 277-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Union Valley
Each reading below is measured for Union Valley itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsUnion Valley runs about 277 days between hard freezes (read from Hunt County, the closest normal to Union Valley) — close to year-round growing.
Frost is rarely the limit here; winter plantings are as real as summer ones, and the harder question is which crops shrug off the summer heat.
Grow cool-season crops through the mild winter, and choose heat-tolerant varieties for the summer beds.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredUnion Valley sits in USDA hardiness zone 8b.
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 Union Valley is in
Union Valley sits in the Texas Blackland Prairies — EPA Level III, inside the wider Great Plains. That is read at Union Valley's own centroid rather than borrowed from Hunt County.
What Grows in Union Valley
Every plant below cleared Union Valley's own zone 8b and its 277-day season. Each card opens that plant's Texas profile. How we score.
Is it too late to plant in Union Valley?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Jan 26; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 23 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 27 — long-season crops need about 90 days of runway, quick greens only 30. With almost year-round growing weather, timing is about heat and rainfall more than frost — some bench is always in play.
What's on the federal record near Union Valley
Closest first, within ~10 miles of Union Valley. Listing isn't leaking, and distance isn't exposure.
- GREEN PLANETBrownfields · 2.2 mi
- FOX AND ASSOCIATES INCBrownfields · 3.0 mi
- XPRESS ONE STOPUnderground Storage Tanks · 3.6 mi
- TIGER MART 29Underground Storage Tanks · 3.8 mi
- ZURN INDUSTRIES, LLC DBA STAINLESSDRAINS.COMToxics Release Inventory · 4.1 mi
- R & E SUPER SERVICEUnderground Storage Tanks · 4.1 mi
- CITY OF ROYSE CITYPFAS · 4.2 mi
- R C H WSCPFAS · 4.2 mi
- CITY OF FATEPFAS · 4.2 mi
- BLACKLAND WSCPFAS · 4.2 mi
- CITY OF JOSEPHINEPFAS · 4.2 mi
- B H P WSCPFAS · 4.2 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Union Valley'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 Union Valley.
Total Sites
93
within ~10 miles of Union Valley
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Union Valley
Severity Distribution
within ~10 miles of Union Valley
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Union Valley, two things run higher than the national average within ~10 miles of Union Valley — PFAS (8 sites) and Toxics Release Inventory (7 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Check your specific parcel in Union Valley
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 Union Valley average
Your land is one point inside Union Valley
Everything above resolves to Union Valley as a whole — one PHZM band, read across 2K acres, with hard-freeze dates borrowed from Hunt County’s record because no 30-year normal resolves at this city’s own centroid. 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 city 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 Union Valley Average
Union Valley Average
- ●USDA Zones 8b, averaged across Union Valley
- ●One soil character for all of Union Valley
- ●Frost dates read at Union Valley's scale: Feb 23 to Nov 27
YOUR Parcel
- ✓Your exact zone, not Union Valley's 8b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Union Valley
Pull a site-specific report for your exact address in Union Valley, Texas — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Union Valley averages can't show:
We read public map data around Union Valley — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Union Valley average
How we know this about Union Valley
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Hunt County’s record, because none resolves here; 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 city grain anywhere on this page — there is no city-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 Union Valley
When does frost risk typically end in Union Valley?
The last hard freeze (28°F) in Union Valley typically lands around Feb 23, 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 Mar 16.
When is the first frost in Union Valley?
The first hard freeze (28°F) in Union Valley typically arrives around Nov 27, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 13, so the watching starts about Oct 28 — about 277 days after the spring freeze cleared.
How long is the growing season in Union Valley?
Measured between 28°F hard freezes, Union Valley sees about 277 frost-free days — roughly Feb 23 through Nov 27, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 16 to Nov 13, about 242 days.
Is the soil safe to grow vegetables in Union Valley?
The federal record around Union Valley is a meaningful one — 93 documented sites, mostly Underground Storage Tanks entries (56), the nearest Brownfields record about 2.2 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.
How do I protect my plants from frost in Union Valley?
From about Oct 28 the job here turns from planting to protecting — the last start even a 30-day crop can finish. As the season closes around the first 28°F hard freeze near Nov 27 (NOAA 1991–2020 climate normals), three moves buy time: row cover or an old sheet over tender plants on still, clear nights; water the soil the afternoon before a freeze, so it holds warmth overnight; and harvest tomatoes, peppers and basil before Nov 27. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Union Valley's scale — its 8b band and its 277-day season. Your yard writes its own version of Union Valley'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 Union Valley’s own scale
5 of the readings below were taken at Union Valley's own scale — the 1,697 acres it covers and 93 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Union Valley's own USDA hardiness band, zones 8bUSDA PHZM 2023
- 93 documented contamination sites on the federal record near Union Valley, the closest Brownfields record about 2.2 miles out from the town centreFederal environmental registers
- Union Valley's boundary and the 1,697 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 8b and a ~277-day seasonGrowable Ground crop-matching engine
- The ecoregion at Union Valley's own centroid, the Texas Blackland PrairiesUS EPA Level III Ecoregions
Inherited from a wider read
- The 28°F hard-freeze dates — Union Valley has no normal of its own, so its county's is the closest measured readfrom Hunt County
- Soil character — no town-scale survey exists, so Union Valley's 1,697 acres read through its county's SSURGO summaryfrom Hunt County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Hunt County
- The growing challenges every Texas grower plans around — written at state scale, so they stay on the state guidefrom Texas
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Hunt County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Union Valley's 1,697 acreswhy one lot differs from the next →
- Which side of Union Valley you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,697 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 2.2 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 Union Valley-wide figureread your own land →
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