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

Planting zone for 37184 — Watertown, TN

ZIP code 37184 (Watertown, Wilson 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 October 28.

Where ZIP 37184 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 frostOct 28

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 Watertown, 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 Watertown, 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 frostOctober 28median — 10% chance by Oct 15

Growing season206 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 26 and returns around November 8.

From the NOAA station Lebanon, TN — 14 miles away, elevation 525 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 37184

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 2 – Sep 16

GarlicPlant cloves · Oct 14 – Nov 18

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 6) and first fall frost (Oct 28) 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 37184 came on Feb 21 — 5 days earlier than the 1991–2020 average (Feb 26).

average
Feb 262026
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 Watertown, TN.

Soil in Watertown, TN

The soil mapped at the center of ZIP 37184 is Barfield — silty clay loam, well drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up

pH6.7neutral; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter5%high

Hydrologic groupDwater soaks in very slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Barfield-Rock outcrop complex, 5 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 37184; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Watertown, TN

Summer high90 °Faverage high, July

Winter low28 °Faverage low, January

Hot days56days a year at 90 °F or more

Freezing nights91nights a year at 32 °F or less

Growing degree days4,688base 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

Precipitation56.8 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: Lebanon, TN (14 mi away); precipitation: Lebanon 2.7 Sse, TN (10 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7b.

370127b

Alexandria, TN · 8 mi

370167b

Auburntown, TN · 9 mi

370907b

Lebanon, TN · 9 mi

385477b

Brush Creek, TN · 9 mi

370717b

Gladeville, TN · 10 mi

371367b

Norene, TN · 10 mi

385637b

Gordonsville, TN · 11 mi

371187b

Milton, TN · 11 mi

Tennessee planting zones →

Questions about 37184

What planting zone is ZIP code 37184?

ZIP code 37184 (Watertown, 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 Watertown, TN?

The median last spring frost (32 °F) near 37184 is April 6; after April 23 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Lebanon station.

When is the first frost in Watertown, TN?

The median first fall frost near 37184 is October 28, giving a median frost-free growing season of 206 days.

When should I plant tomatoes in 37184?

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 37184 get?

About 56.8 inches of precipitation a year (NOAA 1991–2020 normals, Lebanon 2.7 Sse station).

How hot do summers get in Watertown, TN?

The average high peaks at 90 °F in July, with about 56 days a year at 90 °F or more.

What kind of soil does 37184 have?

The USDA soil survey maps Barfield at the center of ZIP 37184: silty clay loam, well drained, pH about 6.7 (neutral).

Did spring come early in Watertown, TN in 2026?

Spring leaf-out near 37184 came on Feb 21 in 2026, 5 days earlier than the 1991–2020 average (Feb 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Watertown, TN?

Intermediate onions: the longest day near 37184 is 14 h 37 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 37184 change?

Yes. The 2012 USDA map put 37184 in zone 7a; the 2023 map puts it in zone 7b. The newer map uses 1991–2020 data and more weather stations.