Seffner, Florida, sits in USDA hardiness zone 9b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
The conditions favor okra, meyer lemon, california poppy, and artichoke, among others — though every individual site edits that list with its own soil, sun, and drainage.
Even in Seffner, 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 Seffner 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 Seffner — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Seffner — the short answer
Seffner, Florida: USDA zone 9b, about 337 days between hard freezes, across 2K acres of town.
- USDA zone
- 9b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Jan 21
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Dec 24
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~337
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 2K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are this town’s own 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 9b is Seffner's average, not your lot's — a low corner or a tree line moves it. Against Seffner's 337-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Seffner
Each reading below is measured for Seffner itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredSeffner runs about 337 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
MeasuredSeffner 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 Seffner is in
Seffner sits in the Southern Coastal Plain — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Seffner's own centroid rather than borrowed from Hillsborough County.
What Grows in Seffner
Every plant below cleared Seffner's own zone 9b and its 337-day season. Each card opens that plant's Florida profile. How we score.
Is it too late to plant in Seffner?
Almost never — the real question is what to plant next. 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 21 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 24 — 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's on the federal record near Seffner
Closest first, within ~10 miles of Seffner. Listing isn't leaking, and distance isn't exposure.
- MARATHON FOOD MARTUnderground Storage Tanks · 2100 ft
- KARIM BUSINESS CORPBrownfields · 2100 ft
- PRIMETIME FOOD STOREUnderground Storage Tanks · 0.6 mi
- SILVESRE FERNANDEZUnderground Storage Tanks · 0.7 mi
- CIRCLE K #2705075Underground Storage Tanks · 0.8 mi
- SEFFNER CHRISTIAN ACADEMYBrownfields · 0.8 mi
- VETS WHOLESALE NURSERY INCUnderground Storage Tanks · 1.0 mi
- CITGO-SEFFNER #476Underground Storage Tanks · 1.0 mi
- AMERIT FLEET SOLUTIONS INCBrownfields · 1.0 mi
- AMAZON.COM SERVICES LLC - DTP7Brownfields · 1.0 mi
- BOWMAN TRUSTUnderground Storage Tanks · 1.0 mi
- VETS NURSERY NEAR DOVER FLNitrate · 1.1 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Seffner'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 Seffner.
Sources Checked
within ~10 miles of Seffner
Severity Distribution
within ~10 miles of Seffner
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Seffner, Superfund runs higher than the national average — 47 sites within ~10 miles of Seffner. That's not a problem with your land — it's information about it.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check your specific parcel in Seffner
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 Seffner average
Your land is one point inside Seffner
Everything above resolves to Seffner as a whole — one PHZM band and one 28°F frost record, read across 2K 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 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 Seffner Average
Seffner Average
- ●USDA Zones 9b, averaged across Seffner
- ●One soil character for all of Seffner
- ●Frost dates read at Seffner's scale: Jan 21 to Dec 24
YOUR Parcel
- ✓Your exact zone, not Seffner's 9b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Seffner
Pull a site-specific report for your exact address in Seffner, Florida — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Seffner averages can't show:
We read public map data around Seffner — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Seffner average
How we know this about Seffner
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 Seffner’s own record; 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 Seffner
When does frost risk typically end in Seffner?
The last hard freeze (28°F) in Seffner typically lands around Jan 21, 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 11.
When is the first frost in Seffner?
The first hard freeze (28°F) in Seffner typically arrives around Dec 24, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Dec 10, so the watching starts about Nov 24 — about 337 days after the spring freeze cleared.
How long is the growing season in Seffner?
Measured between 28°F hard freezes, Seffner sees about 337 frost-free days — roughly Jan 21 through Dec 24, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 11 to Dec 10, about 302 days.
Is the soil safe to grow vegetables in Seffner?
The federal record around Seffner runs heavier than most — 2,226 documented sites, mostly Underground Storage Tanks entries (1,047), the nearest Underground Storage Tanks record about 0.4 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 Seffner?
From about Nov 24 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 24 (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 24. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Seffner's scale — its 9b band and its 337-day season. Your yard writes its own version of Seffner'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 Seffner’s own scale
6 of the readings below were taken at Seffner's own scale — its own ~337-day season between 28°F freezes, the 2,308 acres it covers and 2,226 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Seffner's own USDA hardiness band, zones 9bUSDA PHZM 2023
- Seffner's own 28°F hard-freeze dates, about Jan 21 and Dec 24 and the ~337-day span between themNOAA 1991–2020 Climate Normals
- 2,226 documented contamination sites on the federal record near Seffner, the closest Underground Storage Tanks record about 0.4 miles out from the town centreFederal environmental registers
- Seffner's boundary and the 2,308 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9b and a ~337-day seasonGrowable Ground crop-matching engine
- The ecoregion at Seffner's own centroid, the Southern Coastal PlainUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Seffner's 2,308 acres read through its county's SSURGO summaryfrom Hillsborough County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Hillsborough County
- The growing challenges every Florida grower plans around — written at state scale, so they stay on the state guidefrom Florida
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Hillsborough County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Seffner's 2,308 acreswhy one lot differs from the next →
- Which side of Seffner you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 2,308 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.4 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 Seffner-wide figureread your own land →
More in Florida
Growing region
Nearby growing guides