Conditional — Some Areas
sour orange (zones 9-11) reaches only part of Texas (6b-10b): zones 9-10 are in range, so where you are in the state decides it.
Sour Orange in Texas — the short answer
Sour Orange in Texas: hardy in zones 9–11, full sun.
- Plant zones
- 9-11
- Not verified — NC State Extension Gardener Plant Toolbox lists zones 8a–11b
- Texas zones
- 6b-10b
- USDA PHZM 2023
- Frost window
- Feb 10 - Mar 12 – Nov 18 - Dec 4
- NOAA RCC ACIS 1991-2020, 28°F
- Shortest county season
- 197 days
- NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze
Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS and university Extension sources — per-field provenance varies and is published with the dataset.
Your yard isn't the whole zone.
Texas spans zones 6b-10b, but your yard sits in exactly one — and slope, tree cover, and cold-air pockets nudge it further. Enter your address and we'll score sour orange against your parcel's actual hardiness, soil, and sun.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
No card required · your parcel report in seconds — read in full free for your first 14 days
Texas is not one climate
Texas’s winter-low ladder runs across 254 counties, from zone 6.5 in Dallam County to zone 10 in Willacy County. That is 35°F between the two counties’ average coldest night — the difference between sour orange overwintering in the ground and coming under cover.
The middle half of 254 counties runs 8–9 zones, with a median of 8.5 zones — a 3.5-zone span end to end.
Measured across 254 Texas counties. USDA PHZM 2023, per county. Quartiles are order statistics — every figure shown is a value a real county recorded, not an interpolation. Your own site sits somewhere inside this range; a parcel report resolves where.
Where in Texas Fits Best
Sour Orange is rated for zones 9–11 — a cold floor USDA puts at 20 to 30°F. Against Texas’s 254 counties that band holds in 78 of them, and the line runs at Angelina County (zone 9a), the coldest county still inside it.
Inside zones 9–11
78 counties
- Atascosa County · zone 9a
- Austin County · zone 9a
- Bastrop County · zone 9a
3 of 78 shown
Below the zone 9 floor
176 counties
- Dallam County · zone 6b
- Lipscomb County · zone 6b
- Armstrong County · zone 7a
3 of 176 shown
Winter cold is the limit here — the same plant works in a container that comes under cover.
County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. A zone is a 10°F band of average annual extreme minimum temperature, so the floor above is the band the plant's rating denotes, not a single measured kill point. Slope, shelter and cold-air drainage routinely move a site half a zone either way from its county figure — which is the part only your address resolves.
Even within Texas's zones 6b-10b, county microclimates differ enough to change what thrives. These counties carry the closest zone match for sour orange (USDA PHZM 2023):
Zone Comparison
Sour Orange Needs
- USDA Zones: 9-11
- Sun: Full SunWe haven't confirmed this against a published source yet.
- Picking window: ~28 days of harvestWe haven't confirmed this against a published source yet.
Texas Has
- USDA Zones: 6b-10b
- Last Hard Freeze (28°F): Feb 10 - Mar 12
- First Hard Freeze (28°F): Nov 18 - Dec 4
- Annual Rainfall: 8-56 inches
- Common Soils: Black clay (Blackland Prairie), Sandy loam, Caliche
Plant Zone Range (zones 9-11)
Preferred Soil pH
Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS, and university Extension sources — per-field provenance varies and is published with the dataset. State data: USDA ARS PHZM 2023, NOAA Climate Normals, NRCS SSURGO.
When to Plant Sour Orange in Texas
The frost window
Across Texas, the last spring hard freeze (28°F) clears between Feb 10 and Mar 12, and the first fall hard freeze lands between Nov 18 and Dec 4 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 251-day window you can count on — up to 297 days on a mild site in a kind year. That marks the hard freeze, not the last light frost, so tender transplants usually wait another 2-3 weeks.
Winter standing
Texas runs as cold as USDA zone 6, and no sourced winter-hardiness floor is on record for sour orange, so this page does not state whether it overwinters here — and gives no fall establishment date on the strength of a guess. Whether sour orange is a permanent planting or a replant-every-spring crop for you turns on your own zone within Texas; check its hardiness range against that before treating it as long-lived ground.
Frost window: NOAA Climate Normals 1991-2020. Plant timing fields: Growable Ground Plant Database — frost-free days from FAO ECOCROP, days to harvest from university Extension production guides, and growing-degree-day and chill-hour minimums that are compilation estimates rather than published figures. Your site's own frost dates can run earlier or later than the state range — a parcel report pins them down.
Soil + Drainage Fit
Sour Orange likes near-neutral soil (pH 5.5-8.3). That's the common-ground band across Texas's black clay (blackland prairie) and sandy loam — a soil test confirms it for your site. It will grow across that whole span, but it does best between pH 6 and 7 — worth knowing before you decide whether a Texas soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Texas site is heavier clay or sits in a low spot, a raised bed lifts the roots above wet ground, or work in compost. Drainage need: We haven't confirmed this against a published source yet.
Plant pH requirements: FAO ECOCROP and USDA PLANTS, with the remaining rows from other published sources or Growable Ground compilation. Drainage: FAO ECOCROP, with the remaining rows from other published sources or Growable Ground compilation. Texas soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
Before you plant sour orange for food
Anything you grow to eat takes up what is in the ground it grows in, so what is on record near you is worth knowing before sour orange goes in. What follows is Texas’s documented federal record at state scale — a screening signal, not a soil test, and not a statement about any one lot.
Safe to Grow Here?
What the federal record shows across Texas — and how to grow with it.
We checked the federal record across Texas — 70,645 documented sites across 7 of the 8 source types we track.
The most significant on record: 480 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
Texas carries one of the heavier federal records we track — and that's not a verdict on your yard. Proximity to a documented site is information, not a diagnosis: nothing here says any particular parcel is affected. It does earn one concrete step — before food beds go in the ground, a professional soil test tells you exactly what you're working with, and raised beds of imported, lab-tested soil grow well almost anywhere in the meantime.
Sources Checked
across Texas
Severity Distribution
across Texas
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Texas, PFAS runs higher than the national average — 1,103 sites across Texas. 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.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Sources: EPA, USGS — 950K documented sites tracked nationwide across 8 federal source types.
What Else to Consider for Sour Orange in Texas
Zone compatibility tells you about winter cold survival — but Texas growers also need to think about:
Extreme heat (100F+ days) stresses many crops from June through September
Rainfall varies dramatically — 8 inches in west TX to 56 inches in east TX
Heavy black clay (Blackland Prairie) is difficult to work and drains poorly
Flash drought conditions can develop rapidly even in wet years
What to actually do about these — and the constraints that apply to every Texas grower, not just sour orange — is covered on the Texas growing guide.
Where in Texas Sour Orange Is Zone-Hardy
Sour Orange is rated for USDA zones 9–11. 78 of Texas’s 254 counties fall inside that band. The coldest that does is Angelina County at zone 9a. 176 counties sit below the plant’s zone 9 floor, where an unprotected plant is relying on snow cover and a mild year. Where you are in Texas decides this one.
Across those 254 counties Texas’s winter-low ladder runs from zone 6b in Dallam County to zone 10a in Willacy County — 3.5 USDA zones of spread, which is 35°F between the two counties’ average coldest night of the year. That is why a statewide hardiness answer is where you start and not where you finish.
The planting window moves with it. Dallam County holds its last hard freeze (28°F) until about Apr 12, while Kenedy County is clear by Jan 14 — 88 days apart. Set sour orange out on your county’s date, not the state’s.
County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. County last-freeze dates: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F killing freeze — earlier than the folk 32°F "last frost". Sour Orange’s zone 9–11 band: Not verified — NC State Extension Gardener Plant Toolbox lists zones 8a–11b. A parcel report resolves your address’s own zone and frost dates rather than its county’s.
Pollinator + Wildlife Value
Sour Orange draws honeybees (high value). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, sour orange can only work that bloom inside Texas's frost window — roughly 274 days, opening after the last 28°F freeze (Feb 10 - Mar 12) and closing at the first (Nov 18 - Dec 4), per NOAA Regional Climate Centers ACIS, 1991-2020. Pollinator value: We haven't confirmed this against a published source yet.
Texas Cooperative Extension
For Texas-specific cultivar recommendations, planting calendars, and pest pressure for sour orange, the canonical source is Texas A&M AgriLife Extension Service. Their fact sheets carry the local trial data we can't generalize across 50 states.
Is Sour Orange native to Texas?
No — the USDA PLANTS Database lists Sour Orange as introduced rather than native in the Lower 48, so it is not part of Texas's native flora. It grows here as a garden plant; pairing it with a few Texas natives keeps local pollinators fed too.
Looking for plants that belong here? The Texas growing guide lists plants that USDA PLANTS records growing in Texas and that Kew and NatureServe Explorer both list in its native range, leaving out any that NatureServe flags as exotic there or that our audit holds.
State records: USDA PLANTS Database state-distribution data (presence, not state-level nativity), accessed 2026-10-19.
Common Questions About Growing Sour Orange in Texas
When can I plant Sour Orange in Texas?
Texas's last spring hard freeze (28°F) clears between Feb 10 and Mar 12, and the first fall hard freeze lands between Nov 18 and Dec 4 (NOAA Regional Climate Centers ACIS, 1991-2020). No sourced winter-hardiness floor is on record for Sour Orange, so this page does not state whether it overwinters in Texas and publishes no fall establishment date for it — check its hardiness range against your own zone before treating it as a permanent planting.
What hardiness zone is Sour Orange grown in across Texas?
Texas spans USDA hardiness zones 6b-10b (USDA ARS PHZM 2023). Sour Orange carries a range of zones 9-11, so the overlap zones are where outdoor growing is most reliable.
How many frost-free days does a typical Texas site have?
A typical Texas site sees ~274 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Sour Orange needs 140+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date.
Is Sour Orange native to Texas?
No — the USDA PLANTS Database lists Sour Orange as introduced rather than native in the Lower 48, so it is not part of Texas's native flora. It grows here as a garden plant; pairing it with a few Texas natives keeps local pollinators fed too.
How should I amend the soil for Sour Orange in Texas?
Sour Orange prefers pH 5.5-8.3 and well (dry spells) drainage. We haven't confirmed this against a published source yet. That sits in the common-ground band across Texas soils — a 30-minute soil test from a local Extension lab confirms it for your specific site.
Will Sour Orange actually grow on my specific land in Texas?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores sour orange against your address's mapped soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.
Check your specific parcel in Texas
State-level data is a sketch. Your Growable Ground report scores sour orange against your land's mapped soil, modelled sun, drainage, and frost data — not zone averages.
Three things about your lot that Texas sour orange averages can't show:
We read public map data around Texas — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Texas sour orange average
Explore More
Growing guides for sour orange
Explore Texas county by county
Texas carries 254 counties with their own USDA zone — a sample of the growing pages for sour orange there:
Where else sour orange grows
Sour Orange's zone band crosses state lines — these are the states closest to Texas in winter climate where it also has a page, plus the far ends of its range. Each one re-answers the question with that state's own record.
More to grow in Texas
Texas has a growing page for 1,036 plants — a rotating sample of the rest of the shelf.
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