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

Planting zone for 03448 — Gilsum, NH

ZIP code 03448 (Gilsum, Cheshire County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 14 and the first fall frost October 1.

Where ZIP 03448 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 14

First frostOct 1

2012 zone5b

Was 5b 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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Gilsum, 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 Gilsum, NH

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 14median — 50% chance of a later frost

Safe for tender plantsMay 28only 10% chance of frost after

First fall frostOctober 1median — 10% chance by Sep 18

Growing season138 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 2 and returns around October 10.

From the NOAA station Keene, NH — 7 miles away, elevation 512 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 03448

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 2 – Apr 16

SpinachSow outdoors · Apr 2 – Apr 23

Broccoli, cabbageStart indoors · Mar 5 – Mar 19

Broccoli, cabbageTransplant · Apr 23 – May 7

Onion setsPlant outdoors · Apr 16 – Apr 30

PotatoesPlant outdoors · Apr 23 – May 7

LettuceSow outdoors · Apr 16 – Apr 30

Carrots, beetsSow outdoors · Apr 23 – May 7

TomatoesStart indoors · Mar 19 – Apr 2

TomatoesTransplant · May 21 – Jun 4

Peppers, eggplantStart indoors · Mar 5 – Mar 19

Peppers, eggplantTransplant · May 28 – Jun 11

BeansSow outdoors · May 21 – Jun 4

Sweet cornSow outdoors · May 21 – Jun 4

Cucumbers, squashSow outdoors · May 21 – Jun 4

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 14) 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 03448 came on Apr 12 — 6 days earlier than the 1991–2020 average (Apr 18).

average
Apr 182026
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).

Soil in Gilsum, NH

The soil mapped at the center of ZIP 03448 is Tunbridge — moderately decomposed plant material, well drained.

TextureModerately decomposed plant materialtop layer

pH3.5strongly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter85%high

Hydrologic groupCwater soaks in slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Tunbridge-Lyman-Rock outcrop complex, 15 to 25 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 03448; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Gilsum, NH

Summer high82 °Faverage high, July

Winter low10 °Faverage low, January

Hot days11days a year at 90 °F or more

Freezing nights174nights a year at 32 °F or less

Growing degree days2,165base 50 °F — the season’s usable heat

Longest day15 h 22 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)

Precipitation47.4 inper year, rain and melted snow

Snowfall80 inper year; 106 days with snow on the ground

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Keene, NH (7 mi away); precipitation: Marlow, NH (6 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 03448

What planting zone is ZIP code 03448?

ZIP code 03448 (Gilsum, 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 Gilsum, NH?

The median last spring frost (32 °F) near 03448 is May 14; after May 28 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Keene station.

When is the first frost in Gilsum, NH?

The median first fall frost near 03448 is October 1, giving a median frost-free growing season of 138 days.

When should I plant tomatoes in 03448?

Start tomato seeds indoors around Mar 19 – Apr 2 and set transplants outside around May 21 – Jun 4, one to three weeks after the median last frost.

How much rain and snow does 03448 get?

About 47.4 inches of precipitation a year and 80 inches of snowfall (NOAA 1991–2020 normals, Marlow station).

How hot do summers get in Gilsum, NH?

The average high peaks at 82 °F in July, with about 11 days a year at 90 °F or more.

What kind of soil does 03448 have?

The USDA soil survey maps Tunbridge at the center of ZIP 03448: moderately decomposed plant material, well drained, pH about 3.5 (strongly acidic).

Did spring come early in Gilsum, NH in 2026?

Spring leaf-out near 03448 came on Apr 12 in 2026, 6 days earlier than the 1991–2020 average (Apr 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Gilsum, NH?

Long-day onions: the longest day near 03448 is 15 h 22 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 03448 change?

Yes. The 2012 USDA map put 03448 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.