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

Planting zone for 05404 — Winooski, VT

ZIP code 05404 (Winooski, Chittenden County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is April 29 and the first fall frost October 15.

Where ZIP 05404 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 29
First frostOct 15
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 Winooski, 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 Winooski, VT

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 29median — 50% chance of a later frost
Safe for tender plantsMay 11only 10% chance of frost after
First fall frostOctober 15median — 10% chance by Oct 2
Growing season169 daysfrost-free, median

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

From the NOAA station Burlington Intl Airport, VT — 2 miles away, elevation 331 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 05404

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 18 – Apr 1
SpinachSow outdoors · Mar 18 – Apr 8
Broccoli, cabbageStart indoors · Feb 18 – Mar 4
Broccoli, cabbageTransplant · Apr 8 – Apr 22
Onion setsPlant outdoors · Apr 1 – Apr 15
PotatoesPlant outdoors · Apr 8 – Apr 22
LettuceSow outdoors · Apr 1 – Apr 15
Carrots, beetsSow outdoors · Apr 8 – Apr 22
TomatoesStart indoors · Mar 4 – Mar 18
TomatoesTransplant · May 6 – May 20
Peppers, eggplantStart indoors · Feb 18 – Mar 4
Peppers, eggplantTransplant · May 13 – May 27
BeansSow outdoors · May 6 – May 20
Sweet cornSow outdoors · May 6 – May 20
Cucumbers, squashSow outdoors · May 6 – May 20
Fall lettuce, spinachSow outdoors · Aug 20 – Sep 3
GarlicPlant cloves · Oct 1 – Nov 5
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 29) and first fall frost (Oct 15) 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 05404 came on Apr 16 — 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 Winooski, VT.

Soil in Winooski, VT

The soil mapped at the center of ZIP 05404 is Adams — loamy sand, somewhat excessively drained.

TextureLoamy sanddrains and warms fast; dries out and needs more feeding
pH4.8strongly acidic; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter3.5%moderate
Hydrologic groupAwater soaks in fast
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Adams and Windsor loamy sands, 0 to 5 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 05404; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Winooski, VT

Summer high82 °Faverage high, July
Winter low13 °Faverage low, January
Hot days8days a year at 90 °F or more
Freezing nights145nights a year at 32 °F or less
Growing degree days2,724base 50 °F — the season’s usable heat
Longest day15 h 33 mindaylight on June 21
Shortest day8 h 49 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation37.5 inper year, rain and melted snow
Snowfall88 inper year; 89 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 29 °F, low 13 °F 29°13° JanFebruary: average high 32 °F, low 14 °F 32°14° FebMarch: average high 41 °F, low 24 °F 41°24° MarApril: average high 55 °F, low 36 °F 55°36° AprMay: average high 69 °F, low 48 °F 69°48° MayJune: average high 78 °F, low 57 °F 78°57° JunJuly: average high 82 °F, low 62 °F 82°62° JulAugust: average high 81 °F, low 61 °F 81°61° AugSeptember: average high 73 °F, low 53 °F 73°53° SepOctober: average high 59 °F, low 42 °F 59°42° OctNovember: average high 46 °F, low 32 °F 46°32° NovDecember: average high 35 °F, low 21 °F 35°21° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 2.13 in precipitation, 21.1 in snowfall 2.1❄21 JanFebruary: 1.77 in precipitation, 19.3 in snowfall 1.8❄19 FebMarch: 2.24 in precipitation, 17.5 in snowfall 2.2❄18 MarApril: 3.07 in precipitation, 4.1 in snowfall 3.1❄4 AprMay: 3.76 in precipitation 3.8 MayJune: 4.26 in precipitation 4.3 JunJuly: 4.06 in precipitation 4.1 JulAugust: 3.54 in precipitation 3.5 AugSeptember: 3.67 in precipitation 3.7 SepOctober: 3.83 in precipitation, 0.3 in snowfall 3.8 OctNovember: 2.70 in precipitation, 5.7 in snowfall 2.7❄6 NovDecember: 2.50 in precipitation, 19.5 in snowfall 2.5❄20 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Burlington Intl Airport, VT (2 mi away); precipitation: Burlington Intl Airport, VT (2 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.

054395a
Colchester, VT · <1 mi
054055a
Burlington, VT · 2 mi
054015b
Burlington, VT · 2 mi
054035a
South Burlington, VT · 4 mi
054495a
Colchester, VT · 4 mi
054085b
Burlington, VT · 4 mi
054465b
Colchester, VT · 5 mi
054025a
Burlington, VT · 6 mi

Vermont planting zones →

Questions about 05404

What planting zone is ZIP code 05404?

ZIP code 05404 (Winooski, 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 Winooski, VT?

The median last spring frost (32 °F) near 05404 is April 29; after May 11 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Burlington Intl Airport station.

When is the first frost in Winooski, VT?

The median first fall frost near 05404 is October 15, giving a median frost-free growing season of 169 days.

When should I plant tomatoes in 05404?

Start tomato seeds indoors around Mar 4 – Mar 18 and set transplants outside around May 6 – May 20, one to three weeks after the median last frost.

How much rain and snow does 05404 get?

About 37.5 inches of precipitation a year and 88 inches of snowfall (NOAA 1991–2020 normals, Burlington Intl Airport station).

How hot do summers get in Winooski, VT?

The average high peaks at 82 °F in July, with about 8 days a year at 90 °F or more.

What kind of soil does 05404 have?

The USDA soil survey maps Adams at the center of ZIP 05404: loamy sand, somewhat excessively drained, pH about 4.8 (strongly acidic).

Did spring come early in Winooski, VT in 2026?

Spring leaf-out near 05404 came on Apr 16 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 Winooski, VT?

Long-day onions: the longest day near 05404 is 15 h 33 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).