Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for Chattanooga, TN

Chattanooga, TN is in USDA zones 7b to 8a across its 19 ZIP codes. The median last spring frost is March 31 and the first fall frost November 6.

Chattanooga on the zone map

Outlined: its 15 ZIP code areas · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zones7b–8a5 to 15 °F
ZIP codes19
Last frostMar 31
First frostNov 6
Growing season219 days

7b 2 ZIPs   8a 17 ZIPs

Frost forecast — next 7 nights

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Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in Chattanooga, TN

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMarch 31median — 50% chance of a later frost
Safe for tender plantsApril 18only 10% chance of frost after
First fall frostNovember 6median — 10% chance by Oct 24
Growing season219 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 21 and returns around November 17.

From the NOAA station Lookout Mtn-Point Park, TN, elevation 2,110 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in Chattanooga

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Feb 17 – Mar 3
SpinachSow outdoors · Feb 17 – Mar 10
Broccoli, cabbageStart indoors · Jan 20 – Feb 3
Broccoli, cabbageTransplant · Mar 10 – Mar 24
Onion setsPlant outdoors · Mar 3 – Mar 17
PotatoesPlant outdoors · Mar 10 – Mar 24
LettuceSow outdoors · Mar 3 – Mar 17
Carrots, beetsSow outdoors · Mar 10 – Mar 24
TomatoesStart indoors · Feb 3 – Feb 17
TomatoesTransplant · Apr 7 – Apr 21
Peppers, eggplantStart indoors · Jan 20 – Feb 3
Peppers, eggplantTransplant · Apr 14 – Apr 28
BeansSow outdoors · Apr 7 – Apr 21
Sweet cornSow outdoors · Apr 7 – Apr 21
Cucumbers, squashSow outdoors · Apr 7 – Apr 21
Fall lettuce, spinachSow outdoors · Sep 11 – Sep 25
GarlicPlant cloves · Oct 23 – Nov 27
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 31) and first fall frost (Nov 6) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 37403 came on Feb 18 — about the same time as the 1991–2020 average (Feb 17).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 7b in Tennessee

566 plants native to the lower 48 states, recorded in Tennessee, and rated by the USDA to survive 5 °F or colder — the bottom of zone 7b. Each links to its USDA PLANTS profile.

Trees 82

Shrubs 116

Wildflowers & perennials 184

Grasses 157

Vines 14

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Chattanooga, TN.

Soil in Chattanooga, TN

The soil mapped at the center of ZIP 37403 is Fullerton — gravelly silt loam, well drained.

TextureGravelly silt loama good balance for most vegetables
pH5.0strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter1.5%low — add compost
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Fullerton-Urban land complex, 3 to 40 percent slopes.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 37403; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Chattanooga, TN

Summer high84 °Faverage high, July
Winter low29 °Faverage low, January
Hot days7days a year at 90 °F or more
Freezing nights69nights a year at 32 °F or less
Growing degree days4,113base 50 °F — the season’s usable heat
Longest day14 h 31 mindaylight on June 21
Shortest day9 h 48 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation58.6 inper year, rain and melted snow

Average high and low, by month

20°30°40°50°60°70°80°90°32 °FJanuary: average high 46 °F, low 29 °F 46°29° JanFebruary: average high 49 °F, low 31 °F 49°31° FebMarch: average high 58 °F, low 39 °F 58°39° MarApril: average high 68 °F, low 47 °F 68°47° AprMay: average high 74 °F, low 57 °F 74°57° MayJune: average high 81 °F, low 65 °F 81°65° JunJuly: average high 84 °F, low 67 °F 84°67° JulAugust: average high 82 °F, low 67 °F 82°67° AugSeptember: average high 78 °F, low 61 °F 78°61° SepOctober: average high 67 °F, low 51 °F 67°51° OctNovember: average high 57 °F, low 40 °F 57°40° NovDecember: average high 49 °F, low 32 °F 49°32° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 5.53 in precipitation 5.5 JanFebruary: 5.99 in precipitation 6.0 FebMarch: 5.59 in precipitation 5.6 MarApril: 5.52 in precipitation 5.5 AprMay: 4.31 in precipitation 4.3 MayJune: 4.21 in precipitation 4.2 JunJuly: 4.78 in precipitation 4.8 JulAugust: 3.98 in precipitation 4.0 AugSeptember: 4.92 in precipitation 4.9 SepOctober: 3.78 in precipitation 3.8 OctNovember: 4.62 in precipitation 4.6 NovDecember: 5.37 in precipitation 5.4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Lookout Mtn-Point Park, TN (4 mi away); precipitation: Lookout Mtn-Point Park, TN (4 mi away). Daylight is calculated from latitude.

ZIP codes in Chattanooga

Tennessee planting zones →

Questions about Chattanooga

What planting zone is Chattanooga, TN?

Chattanooga, TN is in USDA hardiness zones 7b to 8a on the 2023 map (7b: 5 to 10 °F; 8a: 10 to 15 °F).

When is the last frost in Chattanooga, TN?

The median last spring frost is March 31 and the median first fall frost is November 6 (NOAA 1991–2020 normals, Lookout Mtn-Point Park station).

When can I plant a garden in Chattanooga, TN?

Cool-season crops like peas and spinach go in around Feb 17 – Mar 10; tomatoes, peppers, beans and squash after about Apr 7, once frost risk has passed.

What kind of onions grow in Chattanooga, TN?

Intermediate onions: the longest day is 14 h 31 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

How much rain and snow does Chattanooga, TN get?

About 58.6 inches of precipitation a year (NOAA 1991–2020 normals).