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

Planting zone for 08869 — Raritan, NJ

ZIP code 08869 (Raritan, Somerset County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 30 and the first fall frost October 20.

Where ZIP 08869 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.

Zone7a0 to 5 °F

Coldest night−17.8 to −15 °C

Last frostApr 30

First frostOct 20

2012 zone6b

Was 6b 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 7a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Raritan, NJ…

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 Raritan, NJ

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 30median — 50% chance of a later frost

Safe for tender plantsMay 14only 10% chance of frost after

First fall frostOctober 20median — 10% chance by Oct 5

Growing season172 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 15 and returns around October 31.

From the NOAA station Somerville 4 Nw, NJ — 3 miles away, elevation 135 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 08869

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 19 – Apr 2

SpinachSow outdoors · Mar 19 – Apr 9

Broccoli, cabbageStart indoors · Feb 19 – Mar 5

Broccoli, cabbageTransplant · Apr 9 – Apr 23

Onion setsPlant outdoors · Apr 2 – Apr 16

PotatoesPlant outdoors · Apr 9 – Apr 23

LettuceSow outdoors · Apr 2 – Apr 16

Carrots, beetsSow outdoors · Apr 9 – Apr 23

TomatoesStart indoors · Mar 5 – Mar 19

TomatoesTransplant · May 7 – May 21

Peppers, eggplantStart indoors · Feb 19 – Mar 5

Peppers, eggplantTransplant · May 14 – May 28

BeansSow outdoors · May 7 – May 21

Sweet cornSow outdoors · May 7 – May 21

Cucumbers, squashSow outdoors · May 7 – May 21

Fall lettuce, spinachSow outdoors · Aug 25 – Sep 8

GarlicPlant cloves · Oct 6 – Nov 10

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 30) and first fall frost (Oct 20) 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 08869 came on Mar 24 — 5 days earlier than the 1991–2020 average (Mar 29).

average
Mar 292026
Mar 24

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 7a in New Jersey

600 plants native to the lower 48 states, recorded in New Jersey, and rated by the USDA to survive 0 °F or colder — the bottom of zone 7a. 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 Raritan, NJ.

Soil in Raritan, NJ

The soil mapped at the center of ZIP 08869 is Penn — 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 matter3%moderate

Hydrologic groupCwater soaks in slowly

Farmland classprime farmlandUSDA classification

Map unit: Penn channery silt loam, 2 to 6 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 08869; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Raritan, NJ

Summer high86 °Faverage high, July

Winter low19 °Faverage low, January

Hot days16days a year at 90 °F or more

Freezing nights137nights a year at 32 °F or less

Growing degree days2,964base 50 °F — the season’s usable heat

Longest day15 h 05 mindaylight on June 21

Shortest day9 h 16 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation46.7 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: Somerville 4 Nw, NJ (3 mi away); precipitation: Somerville 4 Nw, NJ (3 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

088077a

Bridgewater, NJ · 2 mi

088767a

Somerville, NJ · 2 mi

Readington, NJ · 5 mi

079787a

Pluckemin, NJ · 5 mi

088367a

Martinsville, NJ · 5 mi

088447a

Hillsborough, NJ · 5 mi

New Jersey planting zones →

Questions about 08869

What planting zone is ZIP code 08869?

ZIP code 08869 (Raritan, NJ) is in USDA hardiness zone 7a on the 2023 map: the coldest night of an average winter reaches 0 to 5 °F (−17.8 to −15 °C).

When is the last frost in Raritan, NJ?

The median last spring frost (32 °F) near 08869 is April 30; after May 14 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Somerville 4 Nw station.

When is the first frost in Raritan, NJ?

The median first fall frost near 08869 is October 20, giving a median frost-free growing season of 172 days.

When should I plant tomatoes in 08869?

Start tomato seeds indoors around Mar 5 – Mar 19 and set transplants outside around May 7 – May 21, one to three weeks after the median last frost.

How much rain and snow does 08869 get?

About 46.7 inches of precipitation a year (NOAA 1991–2020 normals, Somerville 4 Nw station).

How hot do summers get in Raritan, NJ?

The average high peaks at 86 °F in July, with about 16 days a year at 90 °F or more.

What kind of soil does 08869 have?

The USDA soil survey maps Penn at the center of ZIP 08869: channery silt loam, well drained, pH about 5.0 (strongly acidic).

Did spring come early in Raritan, NJ in 2026?

Spring leaf-out near 08869 came on Mar 24 in 2026, 5 days earlier than the 1991–2020 average (Mar 29), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Raritan, NJ?

Long-day onions: the longest day near 08869 is 15 h 05 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 08869 change?

Yes. The 2012 USDA map put 08869 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.