St. Landry Parish, in Louisiana, sits in USDA hardiness zone 9a — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
A short list that earns its place here — artichoke, fig, california poppy, and cabbage — with any one site's soil, sun, and drainage making the final cut.
St. Landry Parish lies within Acadiana and the Mississippi Delta — a regional growing area with its own character.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
St. Landry Parish holds more than one microclimate.
Soils and elevations shift across St. Landry Parish, 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 St. Landry Parish — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
St. Landry Parish — the short answer
St. Landry Parish, Louisiana: USDA zone 9a, about 306 days between hard freezes, across 591K acres.
- USDA zone
- 9a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 3
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Dec 6
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~306
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 591K 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 St. Landry Parish's average, not your lot's — a low corner or a tree line moves it. Against St. Landry Parish's 306-day season, see what your own ground reads.
Heat and winter chill in St. Landry Parish
Across a year, St. Landry Parish accumulates about 6,633 growing degree days above 50°F, about 337 more than the middle Louisiana county — ahead of 42 of Louisiana’s 64 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 432 hours below 45°F, 180 fewer than the Louisiana middle of 612. 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 St. Landry County
Across St. Landry County, the ground is predominantly Alfisols, where Sharkey, Gallion, and Lebeau are the most extensive named soil series. The soil is generally poorly drained with a silt loam surface. Topsoil pH runs about 5.5–6.8, slightly acidic. Rainfall drains through hydrologic group D soils.
Soil order
Alfisols
Drainage
Poorly drained
Prime farmland
77%
Hydric soils
54%
Soil still varies lot by lot — soil types explained.
How the ground varies across St. Landry Parish
The USDA soil survey maps 46% of St. Landry Parish as poorly drained — but another 52% drains differently: 33% somewhat poorly drained, 14% well drained.
Sharkey is the most extensive named soil at 19% of mapped acres, then Gallion (11%) and Lebeau (10%).
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 St. Landry Parish
Each reading below is measured for St. Landry Parish itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Drainage
MeasuredThe dominant soils across St. Landry Parish are poorly drained, in hydrologic group D — ground that sheds water slowly.
Beds can stay saturated for days after heavy rain, and the roots of most vegetables, berries, and fruit trees suffocate or rot in soil that never drains.
Raised beds or mounded rows lift roots above the wet zone; choose water-tolerant crops for the lowest spots.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across St. Landry Parish runs about pH 5.5–6.8, close to neutral.
This is the range most vegetables prefer — one correction you probably do not have to make, which is genuinely good news for a new bed.
Keep it there with compost rather than lime or sulfur, and only amend if your own soil test says otherwise.
USDA NRCS SSURGO
Season length
MeasuredSt. Landry Parish runs about 306 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
MeasuredSt. Landry Parish 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 St. Landry Parish is in
St. Landry Parish spans 3 EPA Level III ecoregions — Mississippi Alluvial Plain (56%), Western Gulf Coastal Plain (32%) and South Central Plains (13%). Which one your land falls in changes what grows wild there and how the ground behaves, and a county-wide answer cannot tell you which.
What Grows in St. Landry Parish
We scored all 1,086 plants against St. Landry Parish's own USDA zone 9a and its own 306-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 Louisiana profile.
Is it too late to plant in St. Landry Parish?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Jan 6; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 3 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 6 — 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.
Documented around St. Landry Parish
- monarch butterfly2 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in St. Landry Parish
USGS estimates 185,601 lb of Glyphosate on St. Landry Parish farmland in 2019, its largest by weight, ahead of Metolachlor & Metolachlor-s (89,444 lb) and Metolachlor-s (84,856 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 St. Landry County — and how to grow with it.
We checked the federal record across St. Landry County — 1,004 documented sites across 6 of the 9 source types we track.
The most significant on record: 1 Superfund site (none NPL-listed). 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 St. Landry 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 St. Landry Parish
Closest first, across St. Landry County. Listing isn't leaking, and distance isn't exposure.
- Bourgeois Meat MarketUnderground Storage Tanks · 1.5 mi
- FLORIDA GAS TRANS CO 18Brownfields · 1.6 mi
- Treasure Park GroceryUnderground Storage Tanks · 1.6 mi
- Ben Stanford GroceryUnderground Storage Tanks · 1.6 mi
- SL-476Nitrate · 2.1 mi
- SL-475BNitrate · 2.1 mi
- SL-475ANitrate · 2.1 mi
- SL-5618ZNitrate · 2.2 mi
- Charles G Lawson Trucking IncUnderground Storage Tanks · 2.4 mi
- CYPRESS POINT OUTDOORS & MARINEBrownfields · 2.5 mi
- K&Z AUTOBODY AND RESTORATIONS, LLCBrownfields · 2.5 mi
- AT&T (La 1040)Underground Storage Tanks · 2.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from St. Landry Parish'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 St. Landry Parish.
Total Sites
1,004
across St. Landry County
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
across St. Landry County
Severity Distribution
across St. Landry County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around St. Landry Parish, Nitrate runs higher than the national average — 308 sites across St. Landry County. That's not a problem with your land — it's information about it.
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 St. Landry Parish
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 St. Landry Parish average
Your land is one point inside St. Landry Parish
Everything above resolves to St. Landry Parish as a whole — one PHZM band and one county frost record, read across 591K 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 St. Landry Parish Average
St. Landry Parish Average
- ●USDA Zones 9a, averaged across St. Landry Parish
- ●One soil character for all of St. Landry Parish
- ●Frost dates read at St. Landry Parish's scale: Feb 3 to Dec 6
YOUR Parcel
- ✓Your exact zone, not St. Landry Parish's 9a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in St. Landry Parish
Pull a site-specific report for your exact address in St. Landry Parish, Louisiana — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that St. Landry Parish averages can't show:
We read public map data around St. Landry Parish — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the St. Landry Parish average
How we know this about St. Landry Parish
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 St. Landry Parish carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about St. Landry Parish
When does frost risk typically end in St. Landry Parish?
The last hard freeze (28°F) in St. Landry Parish typically lands around Feb 3, 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 24.
How long is the growing season in St. Landry Parish?
Measured between 28°F hard freezes, St. Landry Parish sees about 306 frost-free days — roughly Feb 3 through Dec 6, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 24 to Nov 22, about 271 days.
Is the soil safe to grow vegetables in St. Landry Parish?
The federal record around St. Landry Parish is a meaningful one — 1,004 documented sites, mostly Underground Storage Tanks entries (424), the nearest Underground Storage Tanks record about 1.5 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 St. Landry Parish's scale — its 9a band and its 306-day season. Your yard writes its own version of St. Landry Parish'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 Louisiana's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at St. Landry Parish’s own scale
9 of the readings below were taken at St. Landry Parish's own scale — its own ~306-day span between 28°F freezes, the 3 most extensive soil series mapped here and 1,004 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- St. Landry Parish's own USDA hardiness band, zones 9aUSDA PHZM 2023
- St. Landry Parish's own 28°F hard-freeze dates and its ~306-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in St. Landry ParishUSDA NRCS SSURGO
- 1,004 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Underground Storage Tanks record about 1.5 miles outFederal environmental registers
- St. Landry Parish's boundary and the 590,961 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9a and a ~306-day seasonGrowable Ground crop-matching engine
- The 3 ecoregions St. Landry Parish spans, Mississippi Alluvial Plain the largestUS EPA Level III Ecoregions
- Open occurrence records documented in St. Landry Parish for a tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto St. Landry Parish farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Louisiana grower plans around — written at state scale, so they stay on the state guidefrom Louisiana
What this page can’t tell you
- How the season shifts across St. Landry Parish — the ~306 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 St. Landry Parish's 590,961 acreswhy one lot differs from the next →
- Which of those 1,004 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 St. Landry Parishread your own land →