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

Planting zone for 05458 — Grand Isle, VT

ZIP code 05458 (Grand Isle, Grand Isle County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is April 28 and the first fall frost October 20.

Where ZIP 05458 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.

Zone5a−20 to −15 °F
Coldest night−28.9 to −26.1 °C
Last frostApr 28
First frostOct 20
2012 zone5a

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 5a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Grand Isle, VT…

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 Grand Isle, VT

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 28median — 50% chance of a later frost
Safe for tender plantsMay 10only 10% chance of frost after
First fall frostOctober 20median — 10% chance by Oct 4
Growing season174 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 18 and returns around November 1.

From the NOAA station S Hero, VT — 6 miles away, elevation 112 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 05458

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 17 – Mar 31
SpinachSow outdoors · Mar 17 – Apr 7
Broccoli, cabbageStart indoors · Feb 17 – Mar 3
Broccoli, cabbageTransplant · Apr 7 – Apr 21
Onion setsPlant outdoors · Mar 31 – Apr 14
PotatoesPlant outdoors · Apr 7 – Apr 21
LettuceSow outdoors · Mar 31 – Apr 14
Carrots, beetsSow outdoors · Apr 7 – Apr 21
TomatoesStart indoors · Mar 3 – Mar 17
TomatoesTransplant · May 5 – May 19
Peppers, eggplantStart indoors · Feb 17 – Mar 3
Peppers, eggplantTransplant · May 12 – May 26
BeansSow outdoors · May 5 – May 19
Sweet cornSow outdoors · May 5 – May 19
Cucumbers, squashSow outdoors · May 5 – May 19
Fall lettuce, spinachSow outdoors · Aug 25 – Sep 8
GarlicPlant cloves · Oct 6 – Nov 10
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 28) and first fall frost (Oct 20) 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 05458 came on Apr 17 — about the same time as the 1991–2020 average (Apr 18).

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 5a in Vermont

459 plants native to the lower 48 states, recorded in Vermont, and rated by the USDA to survive −20 °F or colder — the bottom of zone 5a. Each links to its USDA PLANTS profile.

Trees 49

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 92

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °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 °FAmerican hornbeam30 ft · blooms mid spring · low shade tolerance · to −34 °F

Wildflowers & perennials 162

alpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °Falpine sweetvetch2 ft · blooms early summer · high shade tolerance · to −62 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °FAmerican speedwell0.8 ft · blooms mid summer · low shade tolerance · to −38 °F

Grasses 139

American 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 °FBicknell's sedge3 ft · blooms late spring · low shade tolerance · to −38 °F

Vines 6

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 honeysuckle16 ft · blooms late summer · low shade tolerance · to −33 °FVirginia creeper1 ft · blooms late spring · medium shade tolerance · to −28 °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 Grand Isle, VT.

Soil in Grand Isle, VT

The soil mapped at the center of ZIP 05458 is Benson — silt loam, somewhat excessively drained.

TextureSilt loama good balance for most vegetables
pH6.7neutral; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter4%moderate
Hydrologic groupDwater soaks in very slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Benson rocky silt loam, over shaly limestone, 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 05458; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Grand Isle, VT

Summer high82 °Faverage high, July
Winter low11 °Faverage low, January
Hot days6days a year at 90 °F or more
Freezing nights141nights a year at 32 °F or less
Growing degree days2,576base 50 °F — the season’s usable heat
Longest day15 h 35 mindaylight on June 21
Shortest day8 h 48 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation35 inper year, rain and melted snow
Snowfall50 inper year; 81 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 28 °F, low 11 °F 28°11° JanFebruary: average high 31 °F, low 12 °F 31°12° FebMarch: average high 40 °F, low 22 °F 40°22° MarApril: average high 54 °F, low 34 °F 54°34° AprMay: average high 68 °F, low 46 °F 68°46° MayJune: average high 77 °F, low 56 °F 77°56° JunJuly: average high 82 °F, low 62 °F 82°62° JulAugust: average high 80 °F, low 61 °F 80°61° AugSeptember: average high 72 °F, low 53 °F 72°53° SepOctober: average high 58 °F, low 42 °F 58°42° OctNovember: average high 46 °F, low 31 °F 46°31° NovDecember: average high 34 °F, low 21 °F 34°21° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 1.94 in precipitation, 11.4 in snowfall 1.9❄11 JanFebruary: 1.57 in precipitation, 11.6 in snowfall 1.6❄12 FebMarch: 2.02 in precipitation, 10.6 in snowfall 2.0❄11 MarApril: 2.66 in precipitation, 2.2 in snowfall 2.7❄2 AprMay: 3.36 in precipitation 3.4 MayJune: 4.09 in precipitation 4.1 JunJuly: 3.85 in precipitation 3.9 JulAugust: 3.62 in precipitation 3.6 AugSeptember: 3.26 in precipitation 3.3 SepOctober: 3.74 in precipitation, 0.1 in snowfall 3.7 OctNovember: 2.67 in precipitation, 3.3 in snowfall 2.7❄3 NovDecember: 2.21 in precipitation, 10.9 in snowfall 2.2❄11 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: S Hero, VT (6 mi away); precipitation: S Hero, VT (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

054865b
South Hero, VT · 6 mi
054685a
Milton, VT · 8 mi
129015a
Plattsburgh, NY · 9 mi
054745a
North Hero, VT · 9 mi
129035a
Plattsburgh, NY · 9 mi
054815a
Saint Albans Bay, VT · 10 mi
054785a
Saint Albans, VT · 10 mi
054635a
Isle La Motte, VT · 11 mi

Vermont planting zones →

Questions about 05458

What planting zone is ZIP code 05458?

ZIP code 05458 (Grand Isle, VT) is in USDA hardiness zone 5a on the 2023 map: the coldest night of an average winter reaches −20 to −15 °F (−28.9 to −26.1 °C).

When is the last frost in Grand Isle, VT?

The median last spring frost (32 °F) near 05458 is April 28; after May 10 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, S Hero station.

When is the first frost in Grand Isle, VT?

The median first fall frost near 05458 is October 20, giving a median frost-free growing season of 174 days.

When should I plant tomatoes in 05458?

Start tomato seeds indoors around Mar 3 – Mar 17 and set transplants outside around May 5 – May 19, one to three weeks after the median last frost.

How much rain and snow does 05458 get?

About 35 inches of precipitation a year and 50 inches of snowfall (NOAA 1991–2020 normals, S Hero station).

How hot do summers get in Grand Isle, VT?

The average high peaks at 82 °F in July, with about 6 days a year at 90 °F or more.

What kind of soil does 05458 have?

The USDA soil survey maps Benson at the center of ZIP 05458: silt loam, somewhat excessively drained, pH about 6.7 (neutral).

Did spring come early in Grand Isle, VT in 2026?

Spring leaf-out near 05458 came on Apr 17 in 2026, about the same as the 1991–2020 average (Apr 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Grand Isle, VT?

Long-day onions: the longest day near 05458 is 15 h 35 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).