Port O'Connor, Texas, sits in USDA hardiness zone 9b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
A short list that earns its place here — okra, meyer lemon, california poppy, and artichoke — with any one site's soil, sun, and drainage making the final cut.
Even in Port O'Connor, 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 Port O'Connor 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 Port O'Connor — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Port O'Connor — the short answer
Port O'Connor, Texas: USDA zone 9b, about 324 days between hard freezes, across 3K acres of town.
- USDA zone
- 9b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Jan 28
- Calhoun County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 18
- Calhoun County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~324
- Calhoun 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 Calhoun County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9b is Port O'Connor's average, not your lot's — a low corner or a tree line moves it. Against Port O'Connor's 324-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Port O'Connor
Each reading below is measured for Port O'Connor itself — here is what it means for a garden here, and the move an experienced grower makes about it.

Season length
From county recordsPort O'Connor runs about 324 days between hard freezes (read from Calhoun County, the closest normal to Port O'Connor) — 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
MeasuredPort O'Connor 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 Port O'Connor is in
Port O'Connor sits in the Western Gulf Coastal Plain — EPA Level III, inside the wider Great Plains. That is read at Port O'Connor's own centroid rather than borrowed from Calhoun County.
What Grows in Port O'Connor
Every plant below cleared Port O'Connor's own zone 9b and its 324-day season. Each card opens that plant's Texas profile. How we score.






























Is it too late to plant in Port O'Connor?
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 1; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Jan 28 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 18 — 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 Port O'Connor
Closest first, within ~10 miles of Port O'Connor. Listing isn't leaking, and distance isn't exposure.
- PORT O CONNOR SHAMROCKUnderground Storage Tanks · 1300 ft
- SPEEDY STOP 84Underground Storage Tanks · 1400 ft
- COASTAL BEND MARINE & AUTOUnderground Storage Tanks · 2000 ft
- WILLIAM N LEHRERUnderground Storage Tanks · 2400 ft
- AIR LOGISTICSBrownfields · 0.5 mi
- BRAMAN BOAT HOUSEUnderground Storage Tanks · 0.7 mi
- MARTIN OPERATING PTNR PORT O'CONNORBrownfields · 1.4 mi
- MARTIN OPERATING PTNR PORT O'CONNORToxics Release Inventory · 1.4 mi
Measured from Port O'Connor'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 Port O'Connor.
Total Sites
8
within ~10 miles of Port O'Connor
Risk Level
Low
Highest-severity
1 Toxics Release Inventory facility
Sources Checked
within ~10 miles of Port O'Connor
Severity Distribution
within ~10 miles of Port O'Connor
Highest-Severity Sites
Know Before You Grow
- •Underground tanks leak petroleum as they age — near a former filling station, test the soil.
- •Near a brownfield, raised beds of imported soil give your food clean ground.
- •TRI facilities report what they release. Check the wind — downwind beds catch more of it.
Check your specific parcel in Port O'Connor
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 Port O'Connor average
Your land is one point inside Port O'Connor
Everything above resolves to Port O'Connor as a whole — one PHZM band, read across 3K acres, with hard-freeze dates borrowed from Calhoun 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 Port O'Connor Average
Port O'Connor Average
- ●USDA Zones 9b, averaged across Port O'Connor
- ●One soil character for all of Port O'Connor
- ●Frost dates read at Port O'Connor's scale: Jan 28 to Dec 18
YOUR Parcel
- ✓Your exact zone, not Port O'Connor's 9b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Port O'Connor
Pull a site-specific report for your exact address in Port O'Connor, Texas — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Port O'Connor averages can't show:
We read public map data around Port O'Connor — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Port O'Connor average
How we know this about Port O'Connor
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 Calhoun 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 Port O'Connor
When does frost risk typically end in Port O'Connor?
The last hard freeze (28°F) in Port O'Connor typically lands around Jan 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 Feb 18.
When is the first frost in Port O'Connor?
The first hard freeze (28°F) in Port O'Connor typically arrives around Dec 18, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Dec 4, so the watching starts about Nov 18 — about 324 days after the spring freeze cleared.
How long is the growing season in Port O'Connor?
Measured between 28°F hard freezes, Port O'Connor sees about 324 frost-free days — roughly Jan 28 through Dec 18, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 18 to Dec 4, about 289 days.
Is the soil safe to grow vegetables in Port O'Connor?
The federal record around Port O'Connor is light — 8 documented sites across the 9 federal source types we checked, mostly Underground Storage Tanks entries (5), the nearest Underground Storage Tanks record about 0.2 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 I protect my plants from frost in Port O'Connor?
From about Nov 18 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 18 (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 18. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Port O'Connor's scale — its 9b band and its 324-day season. Your yard writes its own version of Port O'Connor'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 Port O'Connor’s own scale
5 of the readings below were taken at Port O'Connor's own scale — the 2,550 acres it covers and 8 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Port O'Connor's own USDA hardiness band, zones 9bUSDA PHZM 2023
- 8 documented contamination sites on the federal record near Port O'Connor, the closest Underground Storage Tanks record about 0.2 miles out from the town centreFederal environmental registers
- Port O'Connor's boundary and the 2,550 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9b and a ~324-day seasonGrowable Ground crop-matching engine
- The ecoregion at Port O'Connor's own centroid, the Western Gulf Coastal PlainUS EPA Level III Ecoregions
Inherited from a wider read
- The 28°F hard-freeze dates — Port O'Connor has no normal of its own, so its county's is the closest measured readfrom Calhoun County
- Soil character — no town-scale survey exists, so Port O'Connor's 2,550 acres read through its county's SSURGO summaryfrom Calhoun County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Calhoun 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 Calhoun County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Port O'Connor's 2,550 acreswhy one lot differs from the next →
- Which side of Port O'Connor you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 2,550 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks 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 Port O'Connor-wide figureread your own land →
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