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

Planting zone for 28731 — Flat Rock, NC

ZIP code 28731 (Flat Rock, Henderson County) is in USDA zone 7b: the coldest winter night averages 5 to 10 °F. The median last spring frost is April 14 and the first fall frost October 25.

Where ZIP 28731 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 14

First frostOct 25

2012 zone7b

Same zone as on the 2012 map. 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 Flat Rock, NC…

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 Flat Rock, NC

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 14median — 50% chance of a later frost

Safe for tender plantsMay 1only 10% chance of frost after

First fall frostOctober 25median — 10% chance by Oct 12

Growing season192 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 2 and returns around November 3.

From the NOAA station Hendersonville 1 Ne, NC — 4 miles away, elevation 2,159 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 28731

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 3 – Mar 17

SpinachSow outdoors · Mar 3 – Mar 24

Broccoli, cabbageStart indoors · Feb 3 – Feb 17

Broccoli, cabbageTransplant · Mar 24 – Apr 7

Onion setsPlant outdoors · Mar 17 – Mar 31

PotatoesPlant outdoors · Mar 24 – Apr 7

LettuceSow outdoors · Mar 17 – Mar 31

Carrots, beetsSow outdoors · Mar 24 – Apr 7

TomatoesStart indoors · Feb 17 – Mar 3

TomatoesTransplant · Apr 21 – May 5

Peppers, eggplantStart indoors · Feb 3 – Feb 17

Peppers, eggplantTransplant · Apr 28 – May 12

BeansSow outdoors · Apr 21 – May 5

Sweet cornSow outdoors · Apr 21 – May 5

Cucumbers, squashSow outdoors · Apr 21 – May 5

Fall lettuce, spinachSow outdoors · Aug 30 – Sep 13

GarlicPlant cloves · Oct 11 – Nov 15

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 14) and first fall frost (Oct 25) 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 28731 came on Feb 22 — about the same time as the 1991–2020 average (Feb 23).

average
Feb 232026
Feb 22

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 North Carolina

596 plants native to the lower 48 states, recorded in North Carolina, 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 Flat Rock, NC.

Soil in Flat Rock, NC

The soil mapped at the center of ZIP 28731 is Hayesville — loam, well drained.

TextureLoama good balance for most vegetables

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

DrainageWell drainednatural drainage class

Organic matter2%moderate

Hydrologic groupCwater soaks in slowly

Farmland classFarmland of statewide importanceUSDA classification

Map unit: Hayesville loam, 7 to 15 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 28731; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Flat Rock, NC

Summer high85 °Faverage high, July

Winter low27 °Faverage low, January

Hot days10days a year at 90 °F or more

Freezing nights88nights a year at 32 °F or less

Growing degree days3,612base 50 °F — the season’s usable heat

Longest day14 h 32 mindaylight on June 21

Shortest day9 h 46 mindaylight on December 21

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

Precipitation61.6 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: Hendersonville 1 Ne, NC (4 mi away); precipitation: East Flat Rock 0.5 Nne, NC (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7b.

287267b

East Flat Rock, NC · 2 mi

Hendersonville, NC · 7 mi

287927b

Hendersonville, NC · 7 mi

287277b

Edneyville, NC · 7 mi

287607b

Naples, NC · 8 mi

North Carolina planting zones →

Questions about 28731

What planting zone is ZIP code 28731?

ZIP code 28731 (Flat Rock, NC) 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 Flat Rock, NC?

The median last spring frost (32 °F) near 28731 is April 14; after May 1 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Hendersonville 1 Ne station.

When is the first frost in Flat Rock, NC?

The median first fall frost near 28731 is October 25, giving a median frost-free growing season of 192 days.

When should I plant tomatoes in 28731?

Start tomato seeds indoors around Feb 17 – Mar 3 and set transplants outside around Apr 21 – May 5, one to three weeks after the median last frost.

How much rain and snow does 28731 get?

About 61.6 inches of precipitation a year (NOAA 1991–2020 normals, East Flat Rock 0.5 Nne station).

How hot do summers get in Flat Rock, NC?

The average high peaks at 85 °F in July, with about 10 days a year at 90 °F or more.

What kind of soil does 28731 have?

The USDA soil survey maps Hayesville at the center of ZIP 28731: loam, well drained, pH about 5.0 (strongly acidic).

Did spring come early in Flat Rock, NC in 2026?

Spring leaf-out near 28731 came on Feb 22 in 2026, about the same as the 1991–2020 average (Feb 23), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Flat Rock, NC?

Intermediate onions: the longest day near 28731 is 14 h 32 min, so day-neutral types bulb best; long-day varieties may not bulb fully.