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

Planting zone for 37853 — Rockford, TN

ZIP code 37853 (Rockford, Blount County) is in USDA zone 7b: the coldest winter night averages 5 to 10 °F. The median last spring frost is April 1 and the first fall frost November 2.

Where ZIP 37853 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 1

First frostNov 2

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 Rockford, 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 Rockford, TN

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 1median — 50% chance of a later frost

Safe for tender plantsApril 17only 10% chance of frost after

First fall frostNovember 2median — 10% chance by Oct 21

Growing season215 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 19 and returns around November 13.

From the NOAA station Knoxville Mcghee Tyson Airport, TN — 4 miles away, elevation 961 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 37853

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 18 – Mar 4

SpinachSow outdoors · Feb 18 – Mar 11

Broccoli, cabbageStart indoors · Jan 21 – Feb 4

Broccoli, cabbageTransplant · Mar 11 – Mar 25

Onion setsPlant outdoors · Mar 4 – Mar 18

PotatoesPlant outdoors · Mar 11 – Mar 25

LettuceSow outdoors · Mar 4 – Mar 18

Carrots, beetsSow outdoors · Mar 11 – Mar 25

TomatoesStart indoors · Feb 4 – Feb 18

TomatoesTransplant · Apr 8 – Apr 22

Peppers, eggplantStart indoors · Jan 21 – Feb 4

Peppers, eggplantTransplant · Apr 15 – Apr 29

BeansSow outdoors · Apr 8 – Apr 22

Sweet cornSow outdoors · Apr 8 – Apr 22

Cucumbers, squashSow outdoors · Apr 8 – Apr 22

Fall lettuce, spinachSow outdoors · Sep 7 – Sep 21

GarlicPlant cloves · Oct 19 – Nov 23

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 1) and first fall frost (Nov 2) 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 37853 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).

Soil in Rockford, TN

The soil mapped at the center of ZIP 37853 is Litz — channery silt loam, well drained.

TextureChannery silt loama good balance for most vegetables

pH5.0strongly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter1.25%low — add compost

Hydrologic groupCwater soaks in slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Litz silt loam, moderately steep phase.

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 37853; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Rockford, TN

Summer high88 °Faverage high, July

Winter low30 °Faverage low, January

Hot days37days a year at 90 °F or more

Freezing nights67nights a year at 32 °F or less

Growing degree days4,664base 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

Precipitation51.9 inper year, rain and melted snow

Snowfall5 inper year; 3 days with snow on the ground

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

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

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7b.

Louisville, TN · 8 mi

379167b

Knoxville, TN · 8 mi

Tennessee planting zones →

Questions about 37853

What planting zone is ZIP code 37853?

ZIP code 37853 (Rockford, 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 Rockford, TN?

The median last spring frost (32 °F) near 37853 is April 1; after April 17 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Knoxville Mcghee Tyson Airport station.

When is the first frost in Rockford, TN?

The median first fall frost near 37853 is November 2, giving a median frost-free growing season of 215 days.

When should I plant tomatoes in 37853?

Start tomato seeds indoors around Feb 4 – Feb 18 and set transplants outside around Apr 8 – Apr 22, one to three weeks after the median last frost.

How much rain and snow does 37853 get?

About 51.9 inches of precipitation a year and 5 inches of snowfall (NOAA 1991–2020 normals, Knoxville Mcghee Tyson Airport station).

How hot do summers get in Rockford, TN?

The average high peaks at 88 °F in July, with about 37 days a year at 90 °F or more.

What kind of soil does 37853 have?

The USDA soil survey maps Litz at the center of ZIP 37853: channery silt loam, well drained, pH about 5.0 (strongly acidic).

Did spring come early in Rockford, TN in 2026?

Spring leaf-out near 37853 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 Rockford, TN?

Intermediate onions: the longest day near 37853 is 14 h 35 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 37853 change?

Yes. The 2012 USDA map put 37853 in zone 7a; the 2023 map puts it in zone 7b. The newer map uses 1991–2020 data and more weather stations.