Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 37375 — Sewanee, TN

ZIP code 37375 (Sewanee, Franklin County) is in USDA zone 7b: the coldest winter night averages 5 to 10 °F. The median last spring frost is April 2 and the first fall frost November 4.

Where ZIP 37375 is

Outlined: the ZIP code area · 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.

Zone7b5 to 10 °F

Coldest night−15 to −12.2 °C

Last frostApr 2

First frostNov 4

2012 zone7a

Was 7a on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 7b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Sewanee, TN…

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 Sewanee, TN

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostApril 2median — 50% chance of a later frost

Safe for tender plantsApril 18only 10% chance of frost after

First fall frostNovember 4median — 10% chance by Oct 22

Growing season216 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 23 and returns around November 16.

From the NOAA station Sewanee, TN — 4 miles away, elevation 1,929 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 37375

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 19 – Mar 5

SpinachSow outdoors · Feb 19 – Mar 12

Broccoli, cabbageStart indoors · Jan 22 – Feb 5

Broccoli, cabbageTransplant · Mar 12 – Mar 26

Onion setsPlant outdoors · Mar 5 – Mar 19

PotatoesPlant outdoors · Mar 12 – Mar 26

LettuceSow outdoors · Mar 5 – Mar 19

Carrots, beetsSow outdoors · Mar 12 – Mar 26

TomatoesStart indoors · Feb 5 – Feb 19

TomatoesTransplant · Apr 9 – Apr 23

Peppers, eggplantStart indoors · Jan 22 – Feb 5

Peppers, eggplantTransplant · Apr 16 – Apr 30

BeansSow outdoors · Apr 9 – Apr 23

Sweet cornSow outdoors · Apr 9 – Apr 23

Cucumbers, squashSow outdoors · Apr 9 – Apr 23

Fall lettuce, spinachSow outdoors · Sep 9 – Sep 23

GarlicPlant cloves · Oct 21 – Nov 25

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 2) and first fall frost (Nov 4) 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 37375 came on Feb 21 — 8 days earlier than the 1991–2020 average (Mar 1).

average
Mar 12026
Feb 21

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.

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 Sewanee, TN.

Soil in Sewanee, TN

The soil mapped at the center of ZIP 37375 is Hartsells — fine sandy loam, well drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding

pH4.6strongly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter1.5%low — add compost

Hydrologic groupCwater soaks in slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Hartsells fine sandy loam, rolling and undulating phases.

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 37375; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Sewanee, TN

Summer high84 °Faverage high, July

Winter low29 °Faverage low, January

Hot days9days a year at 90 °F or more

Freezing nights68nights a year at 32 °F or less

Growing degree days4,084base 50 °F — the season’s usable heat

Longest day14 h 32 mindaylight on June 21

Shortest day9 h 47 mindaylight on December 21

Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully

Precipitation64 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

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

Nearby ZIP codes

1 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

South Pittsburg, TN · 9 mi

373877a

Tracy City, TN · 13 mi

373747b

Sequatchie, TN · 13 mi

All 2 ZIP codes in Sewanee → · Tennessee planting zones →

Questions about 37375

What planting zone is ZIP code 37375?

ZIP code 37375 (Sewanee, TN) is in USDA hardiness zone 7b on the 2023 map: the coldest night of an average winter reaches 5 to 10 °F (−15 to −12.2 °C).

When is the last frost in Sewanee, TN?

The median last spring frost (32 °F) near 37375 is April 2; after April 18 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Sewanee station.

When is the first frost in Sewanee, TN?

The median first fall frost near 37375 is November 4, giving a median frost-free growing season of 216 days.

When should I plant tomatoes in 37375?

Start tomato seeds indoors around Feb 5 – Feb 19 and set transplants outside around Apr 9 – Apr 23, one to three weeks after the median last frost.

How much rain and snow does 37375 get?

About 64 inches of precipitation a year (NOAA 1991–2020 normals, Sewanee station).

How hot do summers get in Sewanee, TN?

The average high peaks at 84 °F in July, with about 9 days a year at 90 °F or more.

What kind of soil does 37375 have?

The USDA soil survey maps Hartsells at the center of ZIP 37375: fine sandy loam, well drained, pH about 4.6 (strongly acidic).

Did spring come early in Sewanee, TN in 2026?

Spring leaf-out near 37375 came on Feb 21 in 2026, 8 days earlier than the 1991–2020 average (Mar 1), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Sewanee, TN?

Intermediate onions: the longest day near 37375 is 14 h 32 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 37375 change?

Yes. The 2012 USDA map put 37375 in zone 7a; the 2023 map puts it in zone 7b. The newer map uses 1991–2020 data and more weather stations.