Harrison, Tennessee, sits in USDA hardiness zone 8a — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
Expect cabbage, fig, california poppy, and collard greens to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Even in Harrison, 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 Harrison 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 Harrison — soil, climate, flood, and parcel records. How we handle your address.
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Harrison — the short answer
Harrison, Tennessee: USDA zone 8a, about 252 days between hard freezes, across 4K acres of town.
- USDA zone
- 8a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 13
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 20
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~252
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 4K 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 8a is Harrison's average, not your lot's — a low corner or a tree line moves it. Against Harrison's 252-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Harrison
Each reading below is measured for Harrison itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredHarrison runs about 252 days between hard freezes — a long growing season.
There is slack for succession plantings and slow-finishing crops: many vegetables can be sown twice, and the heat-lovers have time to ripen fully.
Plan a second sowing of quick crops after the first comes out, and use the fall window most gardeners let sit idle.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredHarrison sits in USDA hardiness zone 8a.
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 Harrison is in
Harrison sits in the Ridge and Valley — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Harrison's own centroid rather than borrowed from Hamilton County.
What Grows in Harrison
Every plant below cleared Harrison's own zone 8a and its 252-day season. Each card opens that plant's Tennessee profile. How we score.
Is it too late to plant in Harrison?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Feb 13; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 13 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 20 — long-season crops need about 90 days of runway, quick greens only 30. Here the season winds down slowly: late sowings, a real autumn harvest, and garlic in the ground before the first hard freeze.
Documented around Harrison
Survey cells within 31 miles of Harrison checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 98 miles off. What to watch for.
What's on the federal record near Harrison
Closest first, within ~10 miles of Harrison. Listing isn't leaking, and distance isn't exposure.
- Chattanooga Yacht ClubUnderground Storage Tanks · 1100 ft
- U S Coast Guard (g-ecv) MooringsUnderground Storage Tanks · 2400 ft
- Dwayne's Lakeshore MarketUnderground Storage Tanks · 0.8 mi
- Nathan's Sports ShopUnderground Storage Tanks · 1.1 mi
- Chevron Usa IncUnderground Storage Tanks · 1.2 mi
- MT ChevronUnderground Storage Tanks · 1.2 mi
- Robert CunninghamUnderground Storage Tanks · 1.2 mi
- Circle K Store No. 4703609Underground Storage Tanks · 1.2 mi
- Golden Gallon #97Underground Storage Tanks · 1.3 mi
- CARTER SHOOTING SUPPLYBrownfields · 1.3 mi
- Mapco #3660Underground Storage Tanks · 1.3 mi
- Mapco Express no. 3536Underground Storage Tanks · 1.6 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Harrison'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 Harrison.
Sources Checked
within ~10 miles of Harrison
Severity Distribution
within ~10 miles of Harrison
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Harrison, two things run higher than the national average within ~10 miles of Harrison — Toxics Release Inventory (75 sites) and Superfund (14 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check your specific parcel in Harrison
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 Harrison average
Your land is one point inside Harrison
Everything above resolves to Harrison as a whole — one PHZM band and one 28°F frost record, read across 4K 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 Harrison Average
Harrison Average
- ●USDA Zones 8a, averaged across Harrison
- ●One soil character for all of Harrison
- ●Frost dates read at Harrison's scale: Mar 13 to Nov 20
YOUR Parcel
- ✓Your exact zone, not Harrison's 8a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Harrison
Pull a site-specific report for your exact address in Harrison, Tennessee — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Harrison averages can't show:
We read public map data around Harrison — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Harrison average
How we know this about Harrison
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 Harrison’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 Harrison
When does frost risk typically end in Harrison?
The last hard freeze (28°F) in Harrison typically lands around Mar 13, 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 Apr 3.
When is the first frost in Harrison?
The first hard freeze (28°F) in Harrison typically arrives around Nov 20, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 6, so the watching starts about Oct 21 — about 252 days after the spring freeze cleared.
How long is the growing season in Harrison?
Measured between 28°F hard freezes, Harrison sees about 252 frost-free days — roughly Mar 13 through Nov 20, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 3 to Nov 6, about 217 days.
Is the soil safe to grow vegetables in Harrison?
The federal record around Harrison is a meaningful one — 915 documented sites, mostly Underground Storage Tanks entries (615), the nearest Underground Storage Tanks record about 0.2 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.
How do I protect my plants from frost in Harrison?
From about Oct 21 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 Nov 20 (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 Nov 20. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Harrison's scale — its 8a band and its 252-day season. Your yard writes its own version of Harrison'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 Harrison’s own scale
7 of the readings below were taken at Harrison's own scale — its own ~252-day season between 28°F freezes, the 4,315 acres it covers and 915 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Harrison's own USDA hardiness band, zones 8aUSDA PHZM 2023
- Harrison's own 28°F hard-freeze dates, about Mar 13 and Nov 20 and the ~252-day span between themNOAA 1991–2020 Climate Normals
- 915 documented contamination sites on the federal record near Harrison, the closest Underground Storage Tanks record about 0.2 miles out from the town centreFederal environmental registers
- Harrison's boundary and the 4,315 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 8a and a ~252-day seasonGrowable Ground crop-matching engine
- The ecoregion at Harrison's own centroid, the Ridge and ValleyUS EPA Level III Ecoregions
- Lanternfly survey cells around Harrison checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Harrison's 4,315 acres read through its county's SSURGO summaryfrom Hamilton County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Hamilton County
- The growing challenges every Tennessee grower plans around — written at state scale, so they stay on the state guidefrom Tennessee
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Hamilton County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Harrison's 4,315 acreswhy one lot differs from the next →
- Which side of Harrison you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 4,315 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 Harrison-wide figureread your own land →
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