Iowa Colony, Texas, sits in USDA hardiness zone 9b — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
Well-matched crops include okra, meyer lemon, california poppy, and artichoke, and the gap between "grows in the area" and "grows in your yard" is closed by soil, sun, and drainage.
Even in Iowa Colony, 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 Iowa Colony 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 Iowa Colony — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Iowa Colony — the short answer
Iowa Colony, Texas: USDA zone 9b, about 321 days between hard freezes, across 7K acres of town.
- USDA zone
- 9b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Jan 26
- Brazoria County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 13
- Brazoria County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~321
- Brazoria County normal — NOAA 1991–2020, nearest to this town
- Town area
- 7K 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 Brazoria County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9b is Iowa Colony's average, not your lot's — a low corner or a tree line moves it. Against Iowa Colony's 321-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Iowa Colony
Each reading below is measured for Iowa Colony itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsIowa Colony runs about 321 days between hard freezes (read from Brazoria County, the closest normal to Iowa Colony) — 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
MeasuredIowa Colony sits in USDA hardiness zone 9b.
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 Iowa Colony is in
Iowa Colony sits in the Western Gulf Coastal Plain — EPA Level III, inside the wider Great Plains. That is read at Iowa Colony's own centroid rather than borrowed from Brazoria County.
What Grows in Iowa Colony
Every plant below cleared Iowa Colony's own zone 9b and its 321-day season. Each card opens that plant's Texas profile. How we score.
Is it too late to plant in Iowa Colony?
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 1; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Jan 26 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 13 — long-season crops need about 90 days of runway, quick greens only 30. In a climate this gentle, “too late” hardly applies — the question becomes which crops prefer the cooler months ahead.
Documented around Iowa Colony
Survey cells within 31 miles of Iowa Colony checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 483 miles off. What to watch for.
What's on the federal record near Iowa Colony
Closest first, within ~10 miles of Iowa Colony. Listing isn't leaking, and distance isn't exposure.
- CVS PHARMACY #11327Brownfields · 0.6 mi
- BIG - M&RS 40609-40612, JULIFF PIG RECEIVERBrownfields · 1.1 mi
- CTS TEXASBrownfields · 2.3 mi
- FORCE ROAD OIL & VACUUM TRUCKUnderground Storage Tanks · 2.5 mi
- FORMER BILLUPS STA 7943Underground Storage Tanks · 2.7 mi
- HANDI PLUS 42Underground Storage Tanks · 3.1 mi
- BLAZE TRANSPORTBrownfields · 3.2 mi
- TPG 279 05Underground Storage Tanks · 3.2 mi
- DIAMOND EXPRESSUnderground Storage Tanks · 3.2 mi
- HANDI STOP 95Underground Storage Tanks · 3.2 mi
- AM PM EXPRESSUnderground Storage Tanks · 3.3 mi
- CEMEX CONSTRUCTION MATERIALS HOUSTON, LLC - ARCOLAToxics Release Inventory · 3.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Iowa Colony'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 Iowa Colony.
Total Sites
223
within ~10 miles of Iowa Colony
Risk Level
High
Highest-severity
3 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Iowa Colony
Severity Distribution
within ~10 miles of Iowa Colony
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Iowa Colony, two things run higher than the national average within ~10 miles of Iowa Colony — PFAS (21 sites) and Superfund (3 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.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check your specific parcel in Iowa Colony
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 Iowa Colony average
Your land is one point inside Iowa Colony
Everything above resolves to Iowa Colony as a whole — one PHZM band, read across 7K acres, with hard-freeze dates borrowed from Brazoria 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 Iowa Colony Average
Iowa Colony Average
- ●USDA Zones 9b, averaged across Iowa Colony
- ●One soil character for all of Iowa Colony
- ●Frost dates read at Iowa Colony's scale: Jan 26 to Dec 13
YOUR Parcel
- ✓Your exact zone, not Iowa Colony's 9b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Iowa Colony
Pull a site-specific report for your exact address in Iowa Colony, Texas — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Iowa Colony averages can't show:
We read public map data around Iowa Colony — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Iowa Colony average
How we know this about Iowa Colony
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 Brazoria 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 Iowa Colony
When does frost risk typically end in Iowa Colony?
The last hard freeze (28°F) in Iowa Colony typically lands around Jan 26, 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 16.
When is the first frost in Iowa Colony?
The first hard freeze (28°F) in Iowa Colony typically arrives around Dec 13, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 29, so the watching starts about Nov 13 — about 321 days after the spring freeze cleared.
How long is the growing season in Iowa Colony?
Measured between 28°F hard freezes, Iowa Colony sees about 321 frost-free days — roughly Jan 26 through Dec 13, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 16 to Nov 29, about 286 days.
Is the soil safe to grow vegetables in Iowa Colony?
The federal record around Iowa Colony runs heavier than most — 223 documented sites, mostly Underground Storage Tanks entries (110), the nearest Brownfields record about 0.6 miles out — so test the soil before planting food in the ground, and raised beds with clean imported soil grow well in the meantime. Even here, proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what's recorded and where.
How do I protect my plants from frost in Iowa Colony?
From about Nov 13 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 13 (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 13. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Iowa Colony's scale — its 9b band and its 321-day season. Your yard writes its own version of Iowa Colony'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 Iowa Colony’s own scale
6 of the readings below were taken at Iowa Colony's own scale — the 7,085 acres it covers and 223 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Iowa Colony's own USDA hardiness band, zones 9bUSDA PHZM 2023
- 223 documented contamination sites on the federal record near Iowa Colony, the closest Brownfields record about 0.6 miles out from the town centreFederal environmental registers
- Iowa Colony's boundary and the 7,085 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9b and a ~321-day seasonGrowable Ground crop-matching engine
- The ecoregion at Iowa Colony's own centroid, the Western Gulf Coastal PlainUS EPA Level III Ecoregions
- Lanternfly survey cells around Iowa Colony checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- The 28°F hard-freeze dates — Iowa Colony has no normal of its own, so its county's is the closest measured readfrom Brazoria County
- Soil character — no town-scale survey exists, so Iowa Colony's 7,085 acres read through its county's SSURGO summaryfrom Brazoria County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Brazoria 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 Brazoria County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Iowa Colony's 7,085 acreswhy one lot differs from the next →
- Which side of Iowa Colony you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 7,085 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 0.6 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 Iowa Colony-wide figureread your own land →
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