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

Planting zone for 37753 — Hartford, TN

ZIP code 37753 (Hartford, Cocke County) is in USDA zone 7b: the coldest winter night averages 5 to 10 °F. The median last spring frost is April 6 and the first fall frost November 1.

Where ZIP 37753 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 6
First frostNov 1
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 Hartford, 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 Hartford, TN

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 6median — 50% chance of a later frost
Safe for tender plantsApril 23only 10% chance of frost after
First fall frostNovember 1median — 10% chance by Oct 20
Growing season210 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 24 and returns around November 13.

From the NOAA station Waterville 2, NC — 3 miles away, elevation 1,431 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 37753

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Feb 23 – Mar 9
SpinachSow outdoors · Feb 23 – Mar 16
Broccoli, cabbageStart indoors · Jan 26 – Feb 9
Broccoli, cabbageTransplant · Mar 16 – Mar 30
Onion setsPlant outdoors · Mar 9 – Mar 23
PotatoesPlant outdoors · Mar 16 – Mar 30
LettuceSow outdoors · Mar 9 – Mar 23
Carrots, beetsSow outdoors · Mar 16 – Mar 30
TomatoesStart indoors · Feb 9 – Feb 23
TomatoesTransplant · Apr 13 – Apr 27
Peppers, eggplantStart indoors · Jan 26 – Feb 9
Peppers, eggplantTransplant · Apr 20 – May 4
BeansSow outdoors · Apr 13 – Apr 27
Sweet cornSow outdoors · Apr 13 – Apr 27
Cucumbers, squashSow outdoors · Apr 13 – Apr 27
Fall lettuce, spinachSow outdoors · Sep 6 – Sep 20
GarlicPlant cloves · Oct 18 – Nov 22
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 6) and first fall frost (Nov 1) 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 37753 came on Feb 26 — 7 days earlier than the 1991–2020 average (Mar 5).

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 Hartford, TN.

Soil in Hartford, TN

The soil mapped at the center of ZIP 37753 is Brasstown — loam, well drained.

TextureLoama good balance for most vegetables
pH5.3strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3%moderate
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Brasstown loam, 12 to 20 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 37753; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Hartford, TN

Summer high86 °Faverage high, July
Winter low29 °Faverage low, January
Hot days19days a year at 90 °F or more
Freezing nights78nights a year at 32 °F or less
Growing degree days4,148base 50 °F — the season’s usable heat
Longest day14 h 35 mindaylight on June 21
Shortest day9 h 43 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation53.9 inper year, rain and melted snow
Snowfall6 inper year; 3 days with snow on the ground

Average high and low, by month

20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 49 °F, low 29 °F 49°29° JanFebruary: average high 53 °F, low 32 °F 53°32° FebMarch: average high 61 °F, low 38 °F 61°38° MarApril: average high 71 °F, low 46 °F 71°46° AprMay: average high 77 °F, low 54 °F 77°54° MayJune: average high 83 °F, low 62 °F 83°62° JunJuly: average high 86 °F, low 65 °F 86°65° JulAugust: average high 85 °F, low 64 °F 85°64° AugSeptember: average high 80 °F, low 59 °F 80°59° SepOctober: average high 70 °F, low 48 °F 70°48° OctNovember: average high 60 °F, low 37 °F 60°37° NovDecember: average high 51 °F, low 32 °F 51°32° Dec

Precipitation by month inches · ❄ = snowfall

0″2″4″6″January: 4.22 in precipitation, 1.9 in snowfall 4.2❄2 JanFebruary: 3.90 in precipitation, 1.3 in snowfall 3.9❄1 FebMarch: 4.72 in precipitation, 1.5 in snowfall 4.7❄2 MarApril: 4.45 in precipitation 4.5 AprMay: 4.56 in precipitation 4.6 MayJune: 6.38 in precipitation 6.4 JunJuly: 6.49 in precipitation 6.5 JulAugust: 4.61 in precipitation 4.6 AugSeptember: 4.00 in precipitation 4.0 SepOctober: 2.74 in precipitation 2.7 OctNovember: 3.44 in precipitation, 0.1 in snowfall 3.4 NovDecember: 4.37 in precipitation, 0.8 in snowfall 4.4❄1 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Waterville 2, NC (3 mi away); precipitation: Waterville 2, NC (3 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

Tennessee planting zones →

Questions about 37753

What planting zone is ZIP code 37753?

ZIP code 37753 (Hartford, 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 Hartford, TN?

The median last spring frost (32 °F) near 37753 is April 6; after April 23 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Waterville 2 station.

When is the first frost in Hartford, TN?

The median first fall frost near 37753 is November 1, giving a median frost-free growing season of 210 days.

When should I plant tomatoes in 37753?

Start tomato seeds indoors around Feb 9 – Feb 23 and set transplants outside around Apr 13 – Apr 27, one to three weeks after the median last frost.

How much rain and snow does 37753 get?

About 53.9 inches of precipitation a year and 6 inches of snowfall (NOAA 1991–2020 normals, Waterville 2 station).

How hot do summers get in Hartford, TN?

The average high peaks at 86 °F in July, with about 19 days a year at 90 °F or more.

What kind of soil does 37753 have?

The USDA soil survey maps Brasstown at the center of ZIP 37753: loam, well drained, pH about 5.3 (strongly acidic).

Did spring come early in Hartford, TN in 2026?

Spring leaf-out near 37753 came on Feb 26 in 2026, 7 days earlier than the 1991–2020 average (Mar 5), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Hartford, TN?

Intermediate onions: the longest day near 37753 is 14 h 35 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 37753 change?

Yes. The 2012 USDA map put 37753 in zone 7a; the 2023 map puts it in zone 7b. The newer map uses 1991–2020 data and more weather stations.