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

Planting zone for 03583 — Jefferson, NH

ZIP code 03583 (Jefferson, Coos County) is in USDA zone 4b: the coldest winter night averages −25 to −20 °F. The median last spring frost is May 8 and the first fall frost October 1.

Where ZIP 03583 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.

Zone4b−25 to −20 °F
Coldest night−31.7 to −28.9 °C
Last frostMay 8
First frostOct 1
2012 zone4b

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 4b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Jefferson, NH…

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 Jefferson, NH

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 8median — 50% chance of a later frost
Safe for tender plantsMay 23only 10% chance of frost after
First fall frostOctober 1median — 10% chance by Sep 16
Growing season146 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 27 and returns around October 16.

From the NOAA station Jefferson, NH — 2 miles away, elevation 1,234 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 03583

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 27 – Apr 10
SpinachSow outdoors · Mar 27 – Apr 17
Broccoli, cabbageStart indoors · Feb 27 – Mar 13
Broccoli, cabbageTransplant · Apr 17 – May 1
Onion setsPlant outdoors · Apr 10 – Apr 24
PotatoesPlant outdoors · Apr 17 – May 1
LettuceSow outdoors · Apr 10 – Apr 24
Carrots, beetsSow outdoors · Apr 17 – May 1
TomatoesStart indoors · Mar 13 – Mar 27
TomatoesTransplant · May 15 – May 29
Peppers, eggplantStart indoors · Feb 27 – Mar 13
Peppers, eggplantTransplant · May 22 – Jun 5
BeansSow outdoors · May 15 – May 29
Sweet cornSow outdoors · May 15 – May 29
Cucumbers, squashSow outdoors · May 15 – May 29
Fall lettuce, spinachSow outdoors · Aug 6 – Aug 20
GarlicPlant cloves · Sep 17 – Oct 22
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 8) and first fall frost (Oct 1) 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 03583 came on Apr 18 — 11 days earlier than the 1991–2020 average (Apr 29).

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 4b in New Hampshire

438 plants native to the lower 48 states, recorded in New Hampshire, and rated by the USDA to survive −25 °F or colder — the bottom of zone 4b. Each links to its USDA PLANTS profile.

Trees 52

Shrubs 83

Wildflowers & perennials 153

Grasses 134

Vines 5

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 Jefferson, NH.

Soil in Jefferson, NH

The soil mapped at the center of ZIP 03583 is Peru — moderately decomposed plant material, moderately well drained.

TextureModerately decomposed plant materialtop layer
pH4.9strongly acidic; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter80%high
Hydrologic groupC/Dslow when drained; wet otherwise
Farmland classNot prime farmlandUSDA classification

Map unit: Peru fine sandy loam, 8 to 15 percent slopes, very stony.

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 03583; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Jefferson, NH

Summer high78 °Faverage high, July
Winter low7 °Faverage low, January
Hot days2days a year at 90 °F or more
Freezing nights173nights a year at 32 °F or less
Growing degree days1,797base 50 °F — the season’s usable heat
Longest day15 h 32 mindaylight on June 21
Shortest day8 h 50 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation41 inper year, rain and melted snow
Snowfall95 inper year; 123 days with snow on the ground

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 26 °F, low 7 °F 26°7° JanFebruary: average high 29 °F, low 9 °F 29°9° FebMarch: average high 38 °F, low 18 °F 38°18° MarApril: average high 51 °F, low 30 °F 51°30° AprMay: average high 64 °F, low 42 °F 64°42° MayJune: average high 73 °F, low 51 °F 73°51° JunJuly: average high 78 °F, low 56 °F 78°56° JulAugust: average high 76 °F, low 54 °F 76°54° AugSeptember: average high 67 °F, low 45 °F 67°45° SepOctober: average high 55 °F, low 37 °F 55°37° OctNovember: average high 42 °F, low 27 °F 42°27° NovDecember: average high 31 °F, low 16 °F 31°16° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 2.51 in precipitation, 20.1 in snowfall 2.5❄20 JanFebruary: 2.28 in precipitation, 19.8 in snowfall 2.3❄20 FebMarch: 2.61 in precipitation, 16.7 in snowfall 2.6❄17 MarApril: 3.36 in precipitation, 6.5 in snowfall 3.4❄7 AprMay: 3.80 in precipitation, 0.5 in snowfall 3.8❄1 MayJune: 4.40 in precipitation 4.4 JunJuly: 4.26 in precipitation 4.3 JulAugust: 3.98 in precipitation 4.0 AugSeptember: 3.34 in precipitation 3.3 SepOctober: 4.29 in precipitation, 1.8 in snowfall 4.3❄2 OctNovember: 2.95 in precipitation, 7.7 in snowfall 3.0❄8 NovDecember: 3.26 in precipitation, 21.7 in snowfall 3.3❄22 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Jefferson, NH (2 mi away); precipitation: Jefferson, NH (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

New Hampshire planting zones →

Questions about 03583

What planting zone is ZIP code 03583?

ZIP code 03583 (Jefferson, NH) is in USDA hardiness zone 4b on the 2023 map: the coldest night of an average winter reaches −25 to −20 °F (−31.7 to −28.9 °C).

When is the last frost in Jefferson, NH?

The median last spring frost (32 °F) near 03583 is May 8; after May 23 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Jefferson station.

When is the first frost in Jefferson, NH?

The median first fall frost near 03583 is October 1, giving a median frost-free growing season of 146 days.

When should I plant tomatoes in 03583?

Start tomato seeds indoors around Mar 13 – Mar 27 and set transplants outside around May 15 – May 29, one to three weeks after the median last frost.

How much rain and snow does 03583 get?

About 41 inches of precipitation a year and 95 inches of snowfall (NOAA 1991–2020 normals, Jefferson station).

How hot do summers get in Jefferson, NH?

The average high peaks at 78 °F in July, with about 2 days a year at 90 °F or more.

What kind of soil does 03583 have?

The USDA soil survey maps Peru at the center of ZIP 03583: moderately decomposed plant material, moderately well drained, pH about 4.9 (strongly acidic).

Did spring come early in Jefferson, NH in 2026?

Spring leaf-out near 03583 came on Apr 18 in 2026, 11 days earlier than the 1991–2020 average (Apr 29), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Jefferson, NH?

Long-day onions: the longest day near 03583 is 15 h 32 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).