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

Planting zone for 03842 — Hampton, NH

ZIP code 03842 (Hampton, Rockingham County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 4 and the first fall frost October 8.

Where ZIP 03842 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.

Zone6a−10 to −5 °F
Coldest night−23.3 to −20.6 °C
Last frostMay 4
First frostOct 8
2012 zone6a

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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Hampton, 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 Hampton, NH

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 4median — 50% chance of a later frost
Safe for tender plantsMay 18only 10% chance of frost after
First fall frostOctober 8median — 10% chance by Sep 27
Growing season157 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 23 and returns around October 21.

From the NOAA station Greenland, NH — 6 miles away, elevation 95 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 03842

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 23 – Apr 6
SpinachSow outdoors · Mar 23 – Apr 13
Broccoli, cabbageStart indoors · Feb 23 – Mar 9
Broccoli, cabbageTransplant · Apr 13 – Apr 27
Onion setsPlant outdoors · Apr 6 – Apr 20
PotatoesPlant outdoors · Apr 13 – Apr 27
LettuceSow outdoors · Apr 6 – Apr 20
Carrots, beetsSow outdoors · Apr 13 – Apr 27
TomatoesStart indoors · Mar 9 – Mar 23
TomatoesTransplant · May 11 – May 25
Peppers, eggplantStart indoors · Feb 23 – Mar 9
Peppers, eggplantTransplant · May 18 – Jun 1
BeansSow outdoors · May 11 – May 25
Sweet cornSow outdoors · May 11 – May 25
Cucumbers, squashSow outdoors · May 11 – May 25
Fall lettuce, spinachSow outdoors · Aug 13 – Aug 27
GarlicPlant cloves · Sep 24 – Oct 29
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 4) and first fall frost (Oct 8) 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 03842 came on Apr 12 — about the same time as the 1991–2020 average (Apr 12).

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 6a in New Hampshire

486 plants native to the lower 48 states, recorded in New Hampshire, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. Each links to its USDA PLANTS profile.

Trees 53

Shrubs 99

Wildflowers & perennials 171

Grasses 142

Vines 7

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 Hampton, NH.

Soil in Hampton, NH

The soil mapped at the center of ZIP 03842 is Hoosic — gravelly fine sandy loam, somewhat excessively drained.

TextureGravelly fine sandy loamdrains and warms fast; dries out and needs more feeding
pH5.0strongly acidic; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter4%moderate
Hydrologic groupAwater soaks in fast
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Hoosic gravelly fine sandy loam, 3 to 8 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 03842; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Hampton, NH

Summer high81 °Faverage high, July
Winter low16 °Faverage low, January
Hot days11days a year at 90 °F or more
Freezing nights143nights a year at 32 °F or less
Growing degree days2,385base 50 °F — the season’s usable heat
Longest day15 h 21 mindaylight on June 21
Shortest day9 h 00 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation52.6 inper year, rain and melted snow
Snowfall63 inper year; 73 days with snow on the ground

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 33 °F, low 16 °F 33°16° JanFebruary: average high 36 °F, low 18 °F 36°18° FebMarch: average high 43 °F, low 25 °F 43°25° MarApril: average high 56 °F, low 35 °F 56°35° AprMay: average high 66 °F, low 45 °F 66°45° MayJune: average high 75 °F, low 54 °F 75°54° JunJuly: average high 81 °F, low 60 °F 81°60° JulAugust: average high 79 °F, low 59 °F 79°59° AugSeptember: average high 72 °F, low 52 °F 72°52° SepOctober: average high 60 °F, low 41 °F 60°41° OctNovember: average high 48 °F, low 31 °F 48°31° NovDecember: average high 38 °F, low 22 °F 38°22° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″6″January: 3.59 in precipitation, 18.6 in snowfall 3.6❄19 JanFebruary: 3.80 in precipitation, 20.5 in snowfall 3.8❄21 FebMarch: 5.02 in precipitation, 10.9 in snowfall 5.0❄11 MarApril: 4.63 in precipitation, 1.4 in snowfall 4.6❄1 AprMay: 4.45 in precipitation 4.5 MayJune: 4.82 in precipitation 4.8 JunJuly: 3.77 in precipitation 3.8 JulAugust: 4.00 in precipitation 4.0 AugSeptember: 4.19 in precipitation 4.2 SepOctober: 5.20 in precipitation, 0.2 in snowfall 5.2 OctNovember: 4.09 in precipitation, 0.8 in snowfall 4.1❄1 NovDecember: 5.03 in precipitation, 10.2 in snowfall 5.0❄10 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Greenland, NH (6 mi away); precipitation: N Hampton, NH (within 1 mile). 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.

All 2 ZIP codes in Hampton → · New Hampshire planting zones →

Questions about 03842

What planting zone is ZIP code 03842?

ZIP code 03842 (Hampton, NH) is in USDA hardiness zone 6a on the 2023 map: the coldest night of an average winter reaches −10 to −5 °F (−23.3 to −20.6 °C).

When is the last frost in Hampton, NH?

The median last spring frost (32 °F) near 03842 is May 4; after May 18 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Greenland station.

When is the first frost in Hampton, NH?

The median first fall frost near 03842 is October 8, giving a median frost-free growing season of 157 days.

When should I plant tomatoes in 03842?

Start tomato seeds indoors around Mar 9 – Mar 23 and set transplants outside around May 11 – May 25, one to three weeks after the median last frost.

How much rain and snow does 03842 get?

About 52.6 inches of precipitation a year and 63 inches of snowfall (NOAA 1991–2020 normals, N Hampton station).

How hot do summers get in Hampton, NH?

The average high peaks at 81 °F in July, with about 11 days a year at 90 °F or more.

What kind of soil does 03842 have?

The USDA soil survey maps Hoosic at the center of ZIP 03842: gravelly fine sandy loam, somewhat excessively drained, pH about 5.0 (strongly acidic).

Did spring come early in Hampton, NH in 2026?

Spring leaf-out near 03842 came on Apr 12 in 2026, about the same as the 1991–2020 average (Apr 12), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Hampton, NH?

Long-day onions: the longest day near 03842 is 15 h 21 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).