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

Planting zone for 03086 — Wilton, NH

ZIP code 03086 (Wilton, Hillsborough) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 10 and the first fall frost October 6.

Where ZIP 03086 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 10
First frostOct 6
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 Wilton, 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 Wilton, NH

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 10median — 50% chance of a later frost
Safe for tender plantsMay 27only 10% chance of frost after
First fall frostOctober 6median — 10% chance by Sep 25
Growing season147 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 26 and returns around October 18.

From the NOAA station Greenville 1 Nne, NH — 4 miles away, elevation 899 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 03086

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 29 – Apr 12
SpinachSow outdoors · Mar 29 – Apr 19
Broccoli, cabbageStart indoors · Mar 1 – Mar 15
Broccoli, cabbageTransplant · Apr 19 – May 3
Onion setsPlant outdoors · Apr 12 – Apr 26
PotatoesPlant outdoors · Apr 19 – May 3
LettuceSow outdoors · Apr 12 – Apr 26
Carrots, beetsSow outdoors · Apr 19 – May 3
TomatoesStart indoors · Mar 15 – Mar 29
TomatoesTransplant · May 17 – May 31
Peppers, eggplantStart indoors · Mar 1 – Mar 15
Peppers, eggplantTransplant · May 24 – Jun 7
BeansSow outdoors · May 17 – May 31
Sweet cornSow outdoors · May 17 – May 31
Cucumbers, squashSow outdoors · May 17 – May 31
Fall lettuce, spinachSow outdoors · Aug 11 – Aug 25
GarlicPlant cloves · Sep 22 – Oct 27
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 10) and first fall frost (Oct 6) 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 03086 came on Apr 12 — 4 days earlier than the 1991–2020 average (Apr 16).

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

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican beech80 ft · blooms mid spring · low shade tolerance · to −44 °FAmerican chestnut115 ft · blooms early summer · high shade tolerance · to −33 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Farborvitae50 ft · blooms mid spring · medium shade tolerance · to −33 °F

Shrubs 99

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falpine bearberry0.5 ft · blooms early spring · medium shade tolerance · to −62 °Falternateleaf dogwood25 ft · blooms mid spring · low shade tolerance · to −47 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °F

Wildflowers & perennials 171

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °Falpine mountainsorrel1 ft · blooms mid summer · medium shade tolerance · to −43 °Falpine sweetvetch2 ft · blooms early summer · high shade tolerance · to −62 °FAmerican alpine speedwell1 ft · blooms summer · medium shade tolerance · to −28 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °F

Grasses 142

alpine timothy1.4 ft · blooms late spring · medium shade tolerance · to −43 °FAmerican beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °Farctic brome3 ft · blooms early summer · low shade tolerance · to −33 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °FBailey's sedge2.1 ft · blooms late spring · low shade tolerance · to −33 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °F

Vines 7

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °Ftrumpet creeper2 ft · blooms summer · high shade tolerance · to −13 °Ftrumpet honeysuckle16 ft · blooms late summer · low shade tolerance · to −33 °F

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 Wilton, NH.

Soil in Wilton, NH

The soil mapped at the center of ZIP 03086 is Marlow — slightly decomposed plant material, well drained.

TextureSlightly 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: Marlow fine sandy loam, 15 to 35 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 03086; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Wilton, NH

Summer high79 °Faverage high, July
Winter low14 °Faverage low, January
Hot days3days a year at 90 °F or more
Freezing nights157nights a year at 32 °F or less
Growing degree days2,103base 50 °F — the season’s usable heat
Longest day15 h 20 mindaylight on June 21
Shortest day9 h 01 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation49.5 inper year, rain and melted snow
Snowfall75 inper year; 97 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 30 °F, low 14 °F 30°14° JanFebruary: average high 34 °F, low 15 °F 34°15° FebMarch: average high 42 °F, low 22 °F 42°22° MarApril: average high 55 °F, low 33 °F 55°33° AprMay: average high 66 °F, low 42 °F 66°42° MayJune: average high 74 °F, low 52 °F 74°52° JunJuly: average high 79 °F, low 58 °F 79°58° JulAugust: average high 78 °F, low 56 °F 78°56° AugSeptember: average high 70 °F, low 49 °F 70°49° SepOctober: average high 58 °F, low 38 °F 58°38° OctNovember: average high 46 °F, low 30 °F 46°30° NovDecember: average high 36 °F, low 20 °F 36°20° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″6″January: 3.42 in precipitation, 19.2 in snowfall 3.4❄19 JanFebruary: 3.28 in precipitation, 19.2 in snowfall 3.3❄19 FebMarch: 4.25 in precipitation, 15.7 in snowfall 4.3❄16 MarApril: 4.35 in precipitation, 2.9 in snowfall 4.3❄3 AprMay: 3.73 in precipitation 3.7 MayJune: 4.26 in precipitation 4.3 JunJuly: 3.64 in precipitation 3.6 JulAugust: 3.84 in precipitation 3.8 AugSeptember: 4.25 in precipitation 4.3 SepOctober: 5.42 in precipitation, 0.4 in snowfall 5.4 OctNovember: 4.11 in precipitation, 1.9 in snowfall 4.1❄2 NovDecember: 4.96 in precipitation, 16.1 in snowfall 5.0❄16 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Greenville 1 Nne, NH (4 mi away); precipitation: Greenville 1 Nne, NH (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

030826a
Lyndeborough, NH · 4 mi
030556a
Milford, NH · 4 mi
030846a
Temple, NH · 6 mi
030486a
Greenville, NH · 6 mi
030576a
Mont Vernon, NH · 6 mi
030336a
Brookline, NH · 7 mi
030716a
New Ipswich, NH · 8 mi
030316a
Amherst, NH · 9 mi

New Hampshire planting zones →

Questions about 03086

What planting zone is ZIP code 03086?

ZIP code 03086 (Wilton, 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 Wilton, NH?

The median last spring frost (32 °F) near 03086 is May 10; after May 27 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Greenville 1 Nne station.

When is the first frost in Wilton, NH?

The median first fall frost near 03086 is October 6, giving a median frost-free growing season of 147 days.

When should I plant tomatoes in 03086?

Start tomato seeds indoors around Mar 15 – Mar 29 and set transplants outside around May 17 – May 31, one to three weeks after the median last frost.

How much rain and snow does 03086 get?

About 49.5 inches of precipitation a year and 75 inches of snowfall (NOAA 1991–2020 normals, Greenville 1 Nne station).

How hot do summers get in Wilton, NH?

The average high peaks at 79 °F in July, with about 3 days a year at 90 °F or more.

What kind of soil does 03086 have?

The USDA soil survey maps Marlow at the center of ZIP 03086: slightly decomposed plant material, well drained, pH about 3.5 (strongly acidic).

Did spring come early in Wilton, NH in 2026?

Spring leaf-out near 03086 came on Apr 12 in 2026, 4 days earlier than the 1991–2020 average (Apr 16), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Wilton, NH?

Long-day onions: the longest day near 03086 is 15 h 20 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 03086 change?

Yes. The 2012 USDA map put 03086 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.