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

Planting zone for 05074 — Thetford, VT

ZIP code 05074 (Thetford, Orange County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is May 9 and the first fall frost October 1.

Where ZIP 05074 is

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 frostMay 9

First frostOct 1

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 Thetford, 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 Thetford, VT

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 9median — 50% chance of a later frost

Safe for tender plantsMay 24only 10% chance of frost after

First fall frostOctober 1median — 10% chance by Sep 21

Growing season143 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 29 and returns around October 10.

From the NOAA station Chelsea 2 Nw, VT — 4 miles away, elevation 1,440 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 05074

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 28 – Apr 11

SpinachSow outdoors · Mar 28 – Apr 18

Broccoli, cabbageStart indoors · Feb 28 – Mar 14

Broccoli, cabbageTransplant · Apr 18 – May 2

Onion setsPlant outdoors · Apr 11 – Apr 25

PotatoesPlant outdoors · Apr 18 – May 2

LettuceSow outdoors · Apr 11 – Apr 25

Carrots, beetsSow outdoors · Apr 18 – May 2

TomatoesStart indoors · Mar 14 – Mar 28

TomatoesTransplant · May 16 – May 30

Peppers, eggplantStart indoors · Feb 28 – Mar 14

Peppers, eggplantTransplant · May 23 – Jun 6

BeansSow outdoors · May 16 – May 30

Sweet cornSow outdoors · May 16 – May 30

Cucumbers, squashSow outdoors · May 16 – May 30

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 9) 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 05074 came on Apr 16 — 11 days earlier than the 1991–2020 average (Apr 27).

average
Apr 272026
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 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.

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 Thetford, VT.

Soil in Thetford, VT

The soil mapped at the center of ZIP 05074 is Tunbridge — fine sandy loam, well drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding

pH4.8strongly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter5%high

Hydrologic groupCwater soaks in slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Tunbridge-Woodstock very rocky fine sandy loams, 8 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 05074; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Thetford, VT

Summer high76 °Faverage high, July

Winter low7 °Faverage low, January

Hot days1days a year at 90 °F or more

Freezing nights176nights a year at 32 °F or less

Growing degree days1,709base 50 °F — the season’s usable heat

Longest day15 h 29 mindaylight on June 21

Shortest day8 h 53 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation42.4 inper year, rain and melted snow

Snowfall89 inper year

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Chelsea 2 Nw, VT (4 mi away); precipitation: Chelsea 2 Nw, VT (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 5a.

Washington, VT · 6 mi

East Randolph, VT · 7 mi

050725a

Strafford, VT · 8 mi

050835a

West Fairlee, VT · 9 mi

Vermont planting zones →

Questions about 05074

What planting zone is ZIP code 05074?

ZIP code 05074 (Thetford, 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 Thetford, VT?

The median last spring frost (32 °F) near 05074 is May 9; after May 24 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Chelsea 2 Nw station.

When is the first frost in Thetford, VT?

The median first fall frost near 05074 is October 1, giving a median frost-free growing season of 143 days.

When should I plant tomatoes in 05074?

Start tomato seeds indoors around Mar 14 – Mar 28 and set transplants outside around May 16 – May 30, one to three weeks after the median last frost.

How much rain and snow does 05074 get?

About 42.4 inches of precipitation a year and 89 inches of snowfall (NOAA 1991–2020 normals, Chelsea 2 Nw station).

How hot do summers get in Thetford, VT?

The average high peaks at 76 °F in July, with about 1 days a year at 90 °F or more.

What kind of soil does 05074 have?

The USDA soil survey maps Tunbridge at the center of ZIP 05074: fine sandy loam, well drained, pH about 4.8 (strongly acidic).

Did spring come early in Thetford, VT in 2026?

Spring leaf-out near 05074 came on Apr 16 in 2026, 11 days earlier than the 1991–2020 average (Apr 27), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Thetford, VT?

Long-day onions: the longest day near 05074 is 15 h 29 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).