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

Planting zone for 07875 — Stillwater, NJ

ZIP code 07875 (Stillwater, Sussex County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 24 and the first fall frost October 16.

Where ZIP 07875 is

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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostApr 24
First frostOct 16
2012 zone6a

Was 6a 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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Stillwater, 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 Stillwater, NJ

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 24median — 50% chance of a later frost
Safe for tender plantsMay 9only 10% chance of frost after
First fall frostOctober 16median — 10% chance by Oct 2
Growing season176 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 10 and returns around October 30.

From the NOAA station Newton, NJ — 6 miles away, elevation 604 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 07875

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 13 – Mar 27
SpinachSow outdoors · Mar 13 – Apr 3
Broccoli, cabbageStart indoors · Feb 13 – Feb 27
Broccoli, cabbageTransplant · Apr 3 – Apr 17
Onion setsPlant outdoors · Mar 27 – Apr 10
PotatoesPlant outdoors · Apr 3 – Apr 17
LettuceSow outdoors · Mar 27 – Apr 10
Carrots, beetsSow outdoors · Apr 3 – Apr 17
TomatoesStart indoors · Feb 27 – Mar 13
TomatoesTransplant · May 1 – May 15
Peppers, eggplantStart indoors · Feb 13 – Feb 27
Peppers, eggplantTransplant · May 8 – May 22
BeansSow outdoors · May 1 – May 15
Sweet cornSow outdoors · May 1 – May 15
Cucumbers, squashSow outdoors · May 1 – May 15
Fall lettuce, spinachSow outdoors · Aug 21 – Sep 4
GarlicPlant cloves · Oct 2 – Nov 6
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 24) and first fall frost (Oct 16) 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 07875 came on Apr 1 — 5 days earlier than the 1991–2020 average (Apr 6).

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 Stillwater, NJ

The soil mapped at the center of ZIP 07875 is Farmington — slightly decomposed plant material, well drained.

TextureSlightly decomposed plant materialtop layer
DrainageWell drainednatural drainage class
Organic matter85%high
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Rock outcrop-Farmington-Galway complex, 8 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 07875; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Stillwater, NJ

Summer high84 °Faverage high, July
Winter low17 °Faverage low, January
Hot days12days a year at 90 °F or more
Freezing nights142nights a year at 32 °F or less
Growing degree days2,902base 50 °F — the season’s usable heat
Longest day15 h 08 mindaylight on June 21
Shortest day9 h 13 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation51.1 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 37 °F, low 17 °F 37°17° JanFebruary: average high 40 °F, low 19 °F 40°19° FebMarch: average high 48 °F, low 28 °F 48°28° MarApril: average high 61 °F, low 38 °F 61°38° AprMay: average high 70 °F, low 48 °F 70°48° MayJune: average high 80 °F, low 57 °F 80°57° JunJuly: average high 84 °F, low 62 °F 84°62° JulAugust: average high 83 °F, low 60 °F 83°60° AugSeptember: average high 75 °F, low 52 °F 75°52° SepOctober: average high 64 °F, low 41 °F 64°41° OctNovember: average high 52 °F, low 32 °F 52°32° NovDecember: average high 41 °F, low 24 °F 41°24° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 3.75 in precipitation 3.8 JanFebruary: 3.01 in precipitation 3.0 FebMarch: 4.09 in precipitation 4.1 MarApril: 3.96 in precipitation 4.0 AprMay: 4.31 in precipitation 4.3 MayJune: 4.61 in precipitation 4.6 JunJuly: 4.95 in precipitation 5.0 JulAugust: 4.93 in precipitation 4.9 AugSeptember: 5.09 in precipitation 5.1 SepOctober: 4.37 in precipitation 4.4 OctNovember: 3.43 in precipitation 3.4 NovDecember: 4.65 in precipitation 4.7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Newton, NJ (6 mi away); precipitation: Frelinghuysen Twp 1.5 Wnw, NJ (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

078556b
Middleville, NJ · <1 mi
078606b
Newton, NJ · 4 mi
078776b
Swartswood, NJ · 4 mi
078466b
Johnsonburg, NJ · 5 mi
078396b
Greendell, NJ · 6 mi
078256b
Blairstown, NJ · 6 mi
078816b
Wallpack Center, NJ · 6 mi
078796b
Tranquility, NJ · 7 mi

New Jersey planting zones →

Questions about 07875

What planting zone is ZIP code 07875?

ZIP code 07875 (Stillwater, NJ) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Stillwater, NJ?

The median last spring frost (32 °F) near 07875 is April 24; after May 9 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Newton station.

When is the first frost in Stillwater, NJ?

The median first fall frost near 07875 is October 16, giving a median frost-free growing season of 176 days.

When should I plant tomatoes in 07875?

Start tomato seeds indoors around Feb 27 – Mar 13 and set transplants outside around May 1 – May 15, one to three weeks after the median last frost.

How much rain and snow does 07875 get?

About 51.1 inches of precipitation a year (NOAA 1991–2020 normals, Frelinghuysen Twp 1.5 Wnw station).

How hot do summers get in Stillwater, NJ?

The average high peaks at 84 °F in July, with about 12 days a year at 90 °F or more.

What kind of soil does 07875 have?

The USDA soil survey maps Farmington at the center of ZIP 07875: slightly decomposed plant material, well drained.

Did spring come early in Stillwater, NJ in 2026?

Spring leaf-out near 07875 came on Apr 1 in 2026, 5 days earlier than the 1991–2020 average (Apr 6), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Stillwater, NJ?

Long-day onions: the longest day near 07875 is 15 h 08 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 07875 change?

Yes. The 2012 USDA map put 07875 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.