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

Planting zone for 29672 — Seneca, SC

ZIP code 29672 (Seneca, Oconee County) is in USDA zone 8a: the coldest winter night averages 10 to 15 °F. The median last spring frost is March 21 and the first fall frost November 11.

Where ZIP 29672 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.

Zone8a10 to 15 °F

Coldest night−12.2 to −9.4 °C

Last frostMar 21

First frostNov 11

2012 zone8a

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 8a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Seneca, SC…

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 Seneca, SC

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMarch 21median — 50% chance of a later frost

Safe for tender plantsApril 7only 10% chance of frost after

First fall frostNovember 11median — 10% chance by Oct 28

Growing season236 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 7 and returns around November 27.

From the NOAA station Clemson Oconee Co. Airport, SC — 6 miles away, elevation 892 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 29672

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 7 – Feb 21

SpinachSow outdoors · Feb 7 – Feb 28

Broccoli, cabbageStart indoors · Jan 10 – Jan 24

Broccoli, cabbageTransplant · Feb 28 – Mar 14

Onion setsPlant outdoors · Feb 21 – Mar 7

PotatoesPlant outdoors · Feb 28 – Mar 14

LettuceSow outdoors · Feb 21 – Mar 7

Carrots, beetsSow outdoors · Feb 28 – Mar 14

TomatoesStart indoors · Jan 24 – Feb 7

TomatoesTransplant · Mar 28 – Apr 11

Peppers, eggplantStart indoors · Jan 10 – Jan 24

Peppers, eggplantTransplant · Apr 4 – Apr 18

BeansSow outdoors · Mar 28 – Apr 11

Sweet cornSow outdoors · Mar 28 – Apr 11

Cucumbers, squashSow outdoors · Mar 28 – Apr 11

Fall lettuce, spinachSow outdoors · Sep 16 – Sep 30

GarlicPlant cloves · Oct 28 – Dec 2

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 21) and first fall frost (Nov 11) 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 29672 came on Feb 17 — 5 days later than the 1991–2020 average (Feb 12).

average
Feb 122026
Feb 17

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 8a in South Carolina

550 plants native to the lower 48 states, recorded in South Carolina, and rated by the USDA to survive 10 °F or colder — the bottom of zone 8a. 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 Seneca, SC.

Soil in Seneca, SC

The soil mapped at the center of ZIP 29672 is Pacolet — sandy loam, well drained.

TextureSandy loamdrains and warms fast; dries out and needs more feeding

pH5.5moderately acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter0.75%low — add compost

Hydrologic groupBwater soaks in moderately

Farmland classNot prime farmlandUSDA classification

Map unit: Cecil sandy loam, 25 to 35 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 29672; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Seneca, SC

Summer high89 °Faverage high, July

Winter low34 °Faverage low, January

Hot days53days a year at 90 °F or more

Freezing nights38nights a year at 32 °F or less

Growing degree days4,946base 50 °F — the season’s usable heat

Longest day14 h 29 mindaylight on June 21

Shortest day9 h 49 mindaylight on December 21

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

Precipitation56.1 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: Clemson Oconee Co. Airport, SC (6 mi away); precipitation: Seneca 5.7 Ene, SC (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

West Union, SC · 5 mi

All 3 ZIP codes in Seneca → · South Carolina planting zones →

Questions about 29672

What planting zone is ZIP code 29672?

ZIP code 29672 (Seneca, SC) is in USDA hardiness zone 8a on the 2023 map: the coldest night of an average winter reaches 10 to 15 °F (−12.2 to −9.4 °C).

When is the last frost in Seneca, SC?

The median last spring frost (32 °F) near 29672 is March 21; after April 7 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Clemson Oconee Co. Airport station.

When is the first frost in Seneca, SC?

The median first fall frost near 29672 is November 11, giving a median frost-free growing season of 236 days.

When should I plant tomatoes in 29672?

Start tomato seeds indoors around Jan 24 – Feb 7 and set transplants outside around Mar 28 – Apr 11, one to three weeks after the median last frost.

How much rain and snow does 29672 get?

About 56.1 inches of precipitation a year (NOAA 1991–2020 normals, Seneca 5.7 Ene station).

How hot do summers get in Seneca, SC?

The average high peaks at 89 °F in July, with about 53 days a year at 90 °F or more.

What kind of soil does 29672 have?

The USDA soil survey maps Pacolet at the center of ZIP 29672: sandy loam, well drained, pH about 5.5 (moderately acidic).

Did spring come early in Seneca, SC in 2026?

Spring leaf-out near 29672 came on Feb 17 in 2026, 5 days later than the 1991–2020 average (Feb 12), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Seneca, SC?

Intermediate onions: the longest day near 29672 is 14 h 29 min, so day-neutral types bulb best; long-day varieties may not bulb fully.