Zavala County, in Texas, sits in USDA hardiness zone 9a — a zone band wide enough that plant choice, not possibility, is the interesting question.
The conditions favor artichoke, fig, california poppy, and cabbage, among others — though every individual site edits that list with its own soil, sun, and drainage.
Zavala County lies within the South Texas Plains / Brush Country (Rio Grande Plains) — a regional growing area with its own character.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Zavala County holds more than one microclimate.
Soils and elevations shift across Zavala 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 Zavala County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Zavala County — the short answer
Zavala County, Texas: USDA zone 9a, about 307 days between hard freezes, across 830K acres.
- USDA zone
- 9a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 4
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Dec 8
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~307
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 830K 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 9a is Zavala County's average, not your lot's — a low corner or a tree line moves it. Against Zavala County's 307-day season, see what your own ground reads.
Heat and winter chill in Zavala County
Across a year, Zavala County accumulates about 7,802 growing degree days above 50°F, about 1,978 more than the middle Texas county — ahead of 233 of Texas’s 254 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.
Winter banks about 358 hours below 45°F, 737 fewer than the Texas middle of 1,095. Chill is what tells a fruit tree its dormancy is over, and it is set by climate rather than by anything you can build.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Zavala County
Across Zavala County, the ground is predominantly Mollisols, where Uvalde, Bookout, and Chacon are the most extensive named soil series. The soil is generally well drained with a clay loam surface. Topsoil pH runs about 7.0–8.0, slightly alkaline. Rainfall drains through hydrologic group C soils.
Soil order
Mollisols
Drainage
Well drained
Prime farmland
11%
Hydric soils
0%
Soil still varies lot by lot — soil types explained.
How the ground varies across Zavala County
The USDA soil survey maps 78% of Zavala County as well drained — but another 21% drains differently: 21% moderately well drained.
Uvalde is the most extensive named soil at 16% of mapped acres, then Bookout (9%) and Chacon (7%).
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 Zavala County
Each reading below is measured for Zavala 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 Zavala 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 Zavala County runs about pH 7.0–8.0, on the alkaline side.
Many vegetables cope, but acid-lovers like blueberries struggle, and iron and manganese lock up above about pH 7.5 — leaves yellow between the veins even in rich soil.
Elemental sulfur and generous organic matter lower pH slowly for the beds that need it; test first so you add only what the soil actually calls for.
USDA NRCS SSURGO

Season length
MeasuredZavala County runs about 307 days between hard freezes — 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
MeasuredZavala County sits in USDA hardiness zone 9a.
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 Zavala County is in
Zavala County sits in the Southern Texas Plains — EPA Level III, inside the wider Great Plains. One consistent ecological setting across the whole county.
What Grows in Zavala County
We scored all 1,086 plants against Zavala County's own USDA zone 9a and its own 307-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 Texas profile.






























Is it too late to plant in Zavala County?
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 Jan 7; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 4 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 8 — long-season crops need about 90 days of runway, quick greens only 30. Here the calendar nearly circles: cool-season crops take the winter shift, and the next window is always close.
Documented around Zavala County
- monarch butterfly264 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Zavala County
USGS estimates 36,710 lb of Glyphosate on Zavala County farmland in 2019, its largest by weight, ahead of 2,4-d (20,787 lb) and Atrazine (8,159 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 Zavala County — and how to grow with it.
We checked the federal record across Zavala County — 66 documented sites across 7 of the 9 source types we track.
The most significant on record: 1 Superfund site. 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 Zavala 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 Zavala County
Closest first, across Zavala County. Listing isn't leaking, and distance isn't exposure.
- LA PRYOR ICE BOX 1Underground Storage Tanks · 600 ft
- AGUIRRE GROCERYUnderground Storage Tanks · 600 ft
- AGRO FARM SERVICEUnderground Storage Tanks · 600 ft
- LES LAFFERE FARMSUnderground Storage Tanks · 600 ft
- CHAPARROSA RANCHUnderground Storage Tanks · 600 ft
- MENDOZAS CONOCOUnderground Storage Tanks · 600 ft
- BATESVILLE SCHOOLUnderground Storage Tanks · 600 ft
- TXDOT LA PRYOR MAINTENANCE OFFICEUnderground Storage Tanks · 600 ft
- FRITZ COLEMAN PROPERTYUnderground Storage Tanks · 600 ft
- ZAVALA 1Underground Storage Tanks · 600 ft
- BAXTERS SERVICE STATIONUnderground Storage Tanks · 600 ft
- LA PRYOR ICE BOX 2Underground Storage Tanks · 600 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Zavala 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 Zavala County.
Sources Checked
across Zavala County
Severity Distribution
across Zavala County
Highest-Severity Sites

A note from Gnorman
What an experienced grower watches for around here
In and around Zavala County, Underground Storage Tanks runs higher than the national average — 47 sites across Zavala County. That's not a problem with your land — it's information about it.
Underground Storage Tanks: Underground storage tanks are the single most common source of soil contamination near homes and gardens.
Use raised beds with imported soil — this eliminates the primary soil-contact pathway.
Check your specific parcel in Zavala 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 Zavala County average
Your land is one point inside Zavala County
Everything above resolves to Zavala County as a whole — one PHZM band and one county frost record, read across 830K 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 Zavala County Average
Zavala County Average
- ●USDA Zones 9a, averaged across Zavala County
- ●One soil character for all of Zavala County
- ●Frost dates read at Zavala County's scale: Feb 4 to Dec 8
YOUR Parcel
- ✓Your exact zone, not Zavala County's 9a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Zavala County
Pull a site-specific report for your exact address in Zavala County, Texas — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Zavala County averages can't show:
We read public map data around Zavala County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Zavala County average
How we know this about Zavala 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 Zavala County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Zavala County
When does frost risk typically end in Zavala County?
The last hard freeze (28°F) in Zavala County typically lands around Feb 4, 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 Feb 25.
How long is the growing season in Zavala County?
Measured between 28°F hard freezes, Zavala County sees about 307 frost-free days — roughly Feb 4 through Dec 8, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 25 to Nov 24, about 272 days.
Is the soil safe to grow vegetables in Zavala County?
The federal record around Zavala County is a meaningful one — 66 documented sites, mostly Underground Storage Tanks entries (47), the nearest Underground Storage Tanks record about 0.1 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 Zavala County's scale — its 9a band and its 307-day season. Your yard writes its own version of Zavala 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 Texas's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Zavala County’s own scale
9 of the readings below were taken at Zavala County's own scale — its own ~307-day span between 28°F freezes, the 3 most extensive soil series mapped here and 66 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Zavala County's own USDA hardiness band, zones 9aUSDA PHZM 2023
- Zavala County's own 28°F hard-freeze dates and its ~307-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Zavala CountyUSDA NRCS SSURGO
- 66 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Underground Storage Tanks record about 0.1 miles outFederal environmental registers
- Zavala County's boundary and the 830,340 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9a and a ~307-day seasonGrowable Ground crop-matching engine
- Zavala County sitting wholly inside the Southern Texas PlainsUS EPA Level III Ecoregions
- Open occurrence records documented in Zavala County for a tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Zavala County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Texas grower plans around — written at state scale, so they stay on the state guidefrom Texas
What this page can’t tell you
- How the season shifts across Zavala County — the ~307 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 Zavala County's 830,340 acreswhy one lot differs from the next →
- Which of those 66 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 Zavala Countyread your own land →
