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

Planting zone for 37719 — Coalfield, TN

ZIP code 37719 (Coalfield, Morgan County) is in USDA zone 7b: the coldest winter night averages 5 to 10 °F. The median last spring frost is April 5 and the first fall frost November 1.

Where ZIP 37719 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 5

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 Coalfield, 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 Coalfield, TN

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 5median — 50% chance of a later frost

Safe for tender plantsApril 19only 10% chance of frost after

First fall frostNovember 1median — 10% chance by Oct 19

Growing season210 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 23 and returns around November 11.

From the NOAA station Oak Ridge Atdd, TN — 10 miles away, elevation 906 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 37719

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 22 – Mar 8

SpinachSow outdoors · Feb 22 – Mar 15

Broccoli, cabbageStart indoors · Jan 25 – Feb 8

Broccoli, cabbageTransplant · Mar 15 – Mar 29

Onion setsPlant outdoors · Mar 8 – Mar 22

PotatoesPlant outdoors · Mar 15 – Mar 29

LettuceSow outdoors · Mar 8 – Mar 22

Carrots, beetsSow outdoors · Mar 15 – Mar 29

TomatoesStart indoors · Feb 8 – Feb 22

TomatoesTransplant · Apr 12 – Apr 26

Peppers, eggplantStart indoors · Jan 25 – Feb 8

Peppers, eggplantTransplant · Apr 19 – May 3

BeansSow outdoors · Apr 12 – Apr 26

Sweet cornSow outdoors · Apr 12 – Apr 26

Cucumbers, squashSow outdoors · Apr 12 – Apr 26

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 5) 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 37719 came on Feb 25 — 6 days earlier than the 1991–2020 average (Mar 3).

average
Mar 32026
Feb 25

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 Coalfield, TN.

Soil in Coalfield, TN

The soil mapped at the center of ZIP 37719 is Allegheny — loam, well drained.

TextureLoama good balance for most vegetables

pH5.3strongly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter2.5%moderate

Hydrologic groupBwater soaks in moderately

Farmland classprime farmlandUSDA classification

Map unit: Allegheny-Cotaco complex, occasionally flooded.

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 37719; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Coalfield, TN

Summer high87 °Faverage high, July

Winter low29 °Faverage low, January

Hot days39days a year at 90 °F or more

Freezing nights75nights a year at 32 °F or less

Growing degree days4,405base 50 °F — the season’s usable heat

Longest day14 h 37 mindaylight on June 21

Shortest day9 h 42 mindaylight on December 21

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

Precipitation58.5 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: Oak Ridge Atdd, TN (10 mi away); precipitation: Oliver Springs 5.6 Sw, TN (4 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.

378407b

Oliver Springs, TN · 5 mi

Briceville, TN · 11 mi

377637b

Kingston, TN · 14 mi

Tennessee planting zones →

Questions about 37719

What planting zone is ZIP code 37719?

ZIP code 37719 (Coalfield, 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 Coalfield, TN?

The median last spring frost (32 °F) near 37719 is April 5; after April 19 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Oak Ridge Atdd station.

When is the first frost in Coalfield, TN?

The median first fall frost near 37719 is November 1, giving a median frost-free growing season of 210 days.

When should I plant tomatoes in 37719?

Start tomato seeds indoors around Feb 8 – Feb 22 and set transplants outside around Apr 12 – Apr 26, one to three weeks after the median last frost.

How much rain and snow does 37719 get?

About 58.5 inches of precipitation a year (NOAA 1991–2020 normals, Oliver Springs 5.6 Sw station).

How hot do summers get in Coalfield, TN?

The average high peaks at 87 °F in July, with about 39 days a year at 90 °F or more.

What kind of soil does 37719 have?

The USDA soil survey maps Allegheny at the center of ZIP 37719: loam, well drained, pH about 5.3 (strongly acidic).

Did spring come early in Coalfield, TN in 2026?

Spring leaf-out near 37719 came on Feb 25 in 2026, 6 days earlier than the 1991–2020 average (Mar 3), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Coalfield, TN?

Intermediate onions: the longest day near 37719 is 14 h 37 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 37719 change?

Yes. The 2012 USDA map put 37719 in zone 7a; the 2023 map puts it in zone 7b. The newer map uses 1991–2020 data and more weather stations.