Jefferson Davis County, in Mississippi, sits in USDA hardiness zone 8b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
The conditions favor cabbage, fig, california poppy, and collard greens, among others — though every individual site edits that list with its own soil, sun, and drainage.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Jefferson Davis County holds more than one microclimate.
Soils and elevations shift across Jefferson Davis County, 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 Jefferson Davis County — soil, climate, flood, and parcel records. How we handle your address.
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Jefferson Davis County — the short answer
Jefferson Davis County, Mississippi: USDA zone 8b, about 286 days between hard freezes, across 261K acres.
- USDA zone
- 8b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 17
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Nov 30
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~286
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 261K 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 8b is Jefferson Davis County's average, not your lot's — a low corner or a tree line moves it. Against Jefferson Davis County's 286-day season, see what your own ground reads.
Heat and winter chill in Jefferson Davis County
Across a year, Jefferson Davis County accumulates about 5,740 growing degree days above 50°F, about 342 more than the middle Mississippi county — ahead of 60 of Mississippi’s 82 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 885 hours below 45°F, 307 fewer than the Mississippi middle of 1,192. 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 Jefferson Davis County
Across Jefferson Davis County, the ground is predominantly Ultisols, where Ruston, Smithdale, and Ora are the most extensive named soil series. The soil is generally well drained with a sandy loam surface. Topsoil pH runs about 5.0, very strongly acidic. Rainfall drains through hydrologic group B soils.
Soil order
Ultisols
Drainage
Well drained
Prime farmland
39%
Hydric soils
3%
Soil still varies lot by lot — soil types explained.
How the ground varies across Jefferson Davis County
The USDA soil survey maps 60% of Jefferson Davis County as well drained — but another 39% drains differently: 27% moderately well drained, 7% somewhat poorly drained.
Ruston is the most extensive named soil at 28% of mapped acres, then Smithdale (27%) and Ora (13%).
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 Jefferson Davis County
Each reading below is measured for Jefferson Davis County itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Drainage
MeasuredThe dominant soils across Jefferson Davis County are well drained, in hydrologic group B — ground that drains quickly.
The upside is soil you can work early in spring and roots that never drown; the cost is that fast-draining ground dries out fast and leaches nutrients away before plants can use them.
Work in compost and mulch to hold moisture and feed, and water more often in short doses than deep and rarely.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Jefferson Davis County runs about pH 5.0, on the acidic side.
Blueberries, potatoes, and rhododendrons thrive in it, but most vegetables start locking out nutrients below about pH 6.0 and grow pale and stunted no matter how much you feed them.
A measured lime application raises pH for the crops that need it — but test first, because the right rate depends on your own soil, not the county average.
USDA NRCS SSURGO
Season length
MeasuredJefferson Davis County runs about 286 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
MeasuredJefferson Davis County sits in USDA hardiness zone 8b.
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 Jefferson Davis County is in
Jefferson Davis County sits in the Southeastern Plains — EPA Level III, inside the wider Eastern Temperate Forests. One consistent ecological setting across the whole county.
What Grows in Jefferson Davis County
We scored all 1,086 plants against Jefferson Davis County's own USDA zone 8b and its own 286-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 Mississippi profile.
Is it too late to plant in Jefferson Davis County?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Jan 20; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 17 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 30 — 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 gets applied to farmland in Jefferson Davis County
USGS estimates 4,180 lb of Glyphosate on Jefferson Davis County farmland in 2019, its largest by weight, ahead of 2,4-d (2,552 lb) and Triclopyr (936 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 Jefferson Davis County — and how to grow with it.
We checked the federal record across Jefferson Davis County — 100 documented sites across 6 of the 9 source types we track.
The most significant on record: 2 Superfund sites (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 Jefferson Davis 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 Jefferson Davis County
Closest first, across Jefferson Davis County. Listing isn't leaking, and distance isn't exposure.
- Magee Oil & Gas CompanyUnderground Storage Tanks · 1.8 mi
- Nelson GroceryUnderground Storage Tanks · 2.6 mi
- A & P Quick StopUnderground Storage Tanks · 2.7 mi
- 065F0002 JEFFERSON DAVISNitrate · 2.7 mi
- Texaco Refining & Marketing IncUnderground Storage Tanks · 2.7 mi
- Dyess GroceryUnderground Storage Tanks · 2.7 mi
- Prentiss Truck StopUnderground Storage Tanks · 3.0 mi
- KIRKLEYS AUTO ELECTRIC COMPANYBrownfields · 3.1 mi
- COULTERS INCBrownfields · 3.2 mi
- Handy Pak #1Underground Storage Tanks · 3.2 mi
- Fast Mart #5Underground Storage Tanks · 3.3 mi
- 84 Minit MartUnderground Storage Tanks · 3.3 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Jefferson Davis County'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 Jefferson Davis County.
Total Sites
100
across Jefferson Davis County
Risk Level
Elevated
Highest-severity
2 Superfund sites (none NPL-listed)
Sources Checked
across Jefferson Davis County
Severity Distribution
across Jefferson Davis County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Jefferson Davis County, Underground Storage Tanks runs higher than the national average — 67 sites across Jefferson Davis County. That's not a problem with your land — it's information about it.
Underground Storage Tanks: Underground storage tanks are the single most common source of soil contamination near homes and gardens.
Use raised beds with imported soil — this eliminates the primary soil-contact pathway.
Check your specific parcel in Jefferson Davis County
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 Jefferson Davis County average
Your land is one point inside Jefferson Davis County
Everything above resolves to Jefferson Davis County as a whole — one PHZM band and one county frost record, read across 261K 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 Jefferson Davis County Average
Jefferson Davis County Average
- ●USDA Zones 8b, averaged across Jefferson Davis County
- ●One soil character for all of Jefferson Davis County
- ●Frost dates read at Jefferson Davis County's scale: Feb 17 to Nov 30
YOUR Parcel
- ✓Your exact zone, not Jefferson Davis County's 8b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Jefferson Davis County
Pull a site-specific report for your exact address in Jefferson Davis County, Mississippi — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Jefferson Davis County averages can't show:
We read public map data around Jefferson Davis County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Jefferson Davis County average
How we know this about Jefferson Davis County
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 Jefferson Davis County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Jefferson Davis County
When does frost risk typically end in Jefferson Davis County?
The last hard freeze (28°F) in Jefferson Davis County typically lands around Feb 17, 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 10.
How long is the growing season in Jefferson Davis County?
Measured between 28°F hard freezes, Jefferson Davis County sees about 286 frost-free days — roughly Feb 17 through Nov 30, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 10 to Nov 16, about 251 days.
Is the soil safe to grow vegetables in Jefferson Davis County?
The federal record around Jefferson Davis County is a meaningful one — 100 documented sites, mostly Underground Storage Tanks entries (67), the nearest Underground Storage Tanks record about 1.8 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 Jefferson Davis County's scale — its 8b band and its 286-day season. Your yard writes its own version of Jefferson Davis County'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 Mississippi's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Jefferson Davis County’s own scale
8 of the readings below were taken at Jefferson Davis County's own scale — its own ~286-day span between 28°F freezes, the 3 most extensive soil series mapped here and 100 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Jefferson Davis County's own USDA hardiness band, zones 8bUSDA PHZM 2023
- Jefferson Davis County's own 28°F hard-freeze dates and its ~286-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Jefferson Davis CountyUSDA NRCS SSURGO
- 100 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Underground Storage Tanks record about 1.8 miles outFederal environmental registers
- Jefferson Davis County's boundary and the 261,405 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 8b and a ~286-day seasonGrowable Ground crop-matching engine
- Jefferson Davis County sitting wholly inside the Southeastern PlainsUS EPA Level III Ecoregions
- Which agricultural compounds go onto Jefferson Davis County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Mississippi grower plans around — written at state scale, so they stay on the state guidefrom Mississippi
What this page can’t tell you
- How the season shifts across Jefferson Davis County — the ~286 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 Jefferson Davis County's 261,405 acreswhy one lot differs from the next →
- Which of those 100 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 Jefferson Davis Countyread your own land →