Knippa, Texas, sits in USDA hardiness zone 9a — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
On paper, artichoke, fig, california poppy, and cabbage all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Even in Knippa, 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 Knippa 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 Knippa — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Knippa — the short answer
Knippa, Texas: USDA zone 9a, about 297 days between hard freezes, across 3K acres of town.
- USDA zone
- 9a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 13
- Uvalde County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 7
- Uvalde County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~297
- Uvalde County normal — NOAA 1991–2020, nearest to this town
- Town area
- 3K 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 Uvalde County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9a is Knippa's average, not your lot's — a low corner or a tree line moves it. Against Knippa's 297-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Knippa
Each reading below is measured for Knippa itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsKnippa runs about 297 days between hard freezes (read from Uvalde County, the closest normal to Knippa) — 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
MeasuredKnippa 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 Knippa is in
Knippa sits in the Southern Texas Plains — EPA Level III, inside the wider Great Plains. That is read at Knippa's own centroid rather than borrowed from Uvalde County.
What Grows in Knippa
Every plant below cleared Knippa's own zone 9a and its 297-day season. Each card opens that plant's Texas profile. How we score.
Is it too late to plant in Knippa?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Jan 16; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 13 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 7 — 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.
What's on the federal record near Knippa
Closest first, within ~10 miles of Knippa. Listing isn't leaking, and distance isn't exposure.
- YP-69-43-6 (H-6-27)Nitrate · 1200 ft
- YP-69-43-603Nitrate · 0.6 mi
- UVALDE COUNTY FARMERS COOPUnderground Storage Tanks · 0.7 mi
- YP-69-43-606Nitrate · 0.8 mi
- YP-69-43-6XXNitrate · 0.8 mi
- SOUTHWEST TEXAS AQ EQUnderground Storage Tanks · 1.0 mi
- KNIPPA WSCPFAS · 2.5 mi
- YP-69-43-8 (H-5-181)Nitrate · 2.7 mi
- YP-69-44-402Nitrate · 2.9 mi
- YP-69-43-309Nitrate · 2.9 mi
- YP-69-43-302Nitrate · 2.9 mi
- YP-69-43-303Nitrate · 3.2 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Knippa'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 Knippa.
Total Sites
204
within ~10 miles of Knippa
Risk Level
Elevated
Highest-severity
1 concentrated animal feeding operation
Sources Checked
within ~10 miles of Knippa
Severity Distribution
within ~10 miles of Knippa
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Knippa, Nitrate runs higher than the national average — 124 sites within ~10 miles of Knippa. 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 Knippa
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 Knippa average
Your land is one point inside Knippa
Everything above resolves to Knippa as a whole — one PHZM band, read across 3K acres, with hard-freeze dates borrowed from Uvalde County’s record because no 30-year normal resolves at this town’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 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 Knippa Average
Knippa Average
- ●USDA Zones 9a, averaged across Knippa
- ●One soil character for all of Knippa
- ●Frost dates read at Knippa's scale: Feb 13 to Dec 7
YOUR Parcel
- ✓Your exact zone, not Knippa's 9a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Knippa
Pull a site-specific report for your exact address in Knippa, Texas — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Knippa averages can't show:
We read public map data around Knippa — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Knippa average
How we know this about Knippa
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 Uvalde 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 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 Knippa
When does frost risk typically end in Knippa?
The last hard freeze (28°F) in Knippa typically lands around Feb 13, 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 6.
When is the first frost in Knippa?
The first hard freeze (28°F) in Knippa typically arrives around Dec 7, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 23, so the watching starts about Nov 7 — about 297 days after the spring freeze cleared.
How long is the growing season in Knippa?
Measured between 28°F hard freezes, Knippa sees about 297 frost-free days — roughly Feb 13 through Dec 7, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 6 to Nov 23, about 262 days.
Is the soil safe to grow vegetables in Knippa?
The federal record around Knippa is a meaningful one — 204 documented sites, mostly Nitrate entries (124), the nearest Nitrate record about 0.2 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 Knippa?
From about Nov 7 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 Dec 7 (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 Dec 7. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Knippa's scale — its 9a band and its 297-day season. Your yard writes its own version of Knippa'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 Knippa’s own scale
5 of the readings below were taken at Knippa's own scale — the 3,273 acres it covers and 204 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Knippa's own USDA hardiness band, zones 9aUSDA PHZM 2023
- 204 documented contamination sites on the federal record near Knippa, the closest Nitrate record about 0.2 miles out from the town centreFederal environmental registers
- Knippa's boundary and the 3,273 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9a and a ~297-day seasonGrowable Ground crop-matching engine
- The ecoregion at Knippa's own centroid, the Southern Texas PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- The 28°F hard-freeze dates — Knippa has no normal of its own, so its county's is the closest measured readfrom Uvalde County
- Soil character — no town-scale survey exists, so Knippa's 3,273 acres read through its county's SSURGO summaryfrom Uvalde County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Uvalde 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 Uvalde County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Knippa's 3,273 acreswhy one lot differs from the next →
- Which side of Knippa you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 3,273 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 Knippa-wide figureread your own land →