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

Planting zone for 04239 — Jay, ME

ZIP code 04239 (Jay, Franklin County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is May 11 and the first fall frost September 29.

Where ZIP 04239 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 frostMay 11
First frostSep 29
2012 zone4b

Was 4b 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 5a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Jay, ME…

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 Jay, ME

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 11median — 50% chance of a later frost
Safe for tender plantsMay 24only 10% chance of frost after
First fall frostSeptember 29median — 10% chance by Sep 16
Growing season138 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 30 and returns around October 8.

From the NOAA station Livermore Falls 1 E, ME — 4 miles away, elevation 381 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 04239

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 30 – Apr 13
SpinachSow outdoors · Mar 30 – Apr 20
Broccoli, cabbageStart indoors · Mar 2 – Mar 16
Broccoli, cabbageTransplant · Apr 20 – May 4
Onion setsPlant outdoors · Apr 13 – Apr 27
PotatoesPlant outdoors · Apr 20 – May 4
LettuceSow outdoors · Apr 13 – Apr 27
Carrots, beetsSow outdoors · Apr 20 – May 4
TomatoesStart indoors · Mar 16 – Mar 30
TomatoesTransplant · May 18 – Jun 1
Peppers, eggplantStart indoors · Mar 2 – Mar 16
Peppers, eggplantTransplant · May 25 – Jun 8
BeansSow outdoors · May 18 – Jun 1
Sweet cornSow outdoors · May 18 – Jun 1
Cucumbers, squashSow outdoors · May 18 – Jun 1
Fall lettuce, spinachSow outdoors · Aug 4 – Aug 18
GarlicPlant cloves · Sep 15 – Oct 20
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 11) and first fall frost (Sep 29) 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 04239 came on Apr 17 — 7 days earlier than the 1991–2020 average (Apr 24).

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 Maine

483 plants native to the lower 48 states, recorded in Maine, and rated by the USDA to survive −20 °F or colder — the bottom of zone 5a. 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 96

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 166

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °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 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °F

Grasses 151

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 °Fbeaked spikerush3 ft · blooms late spring · high shade tolerance · to −28 °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 Jay, ME.

Soil in Jay, ME

The soil mapped at the center of ZIP 04239 is Colonel — highly decomposed plant material, somewhat poorly drained.

TextureHighly decomposed plant materialtop layer
pH5.0strongly acidic; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter85%high
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Colonel-Peru association, 3 to 15 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 04239; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Jay, ME

Summer high80 °Faverage high, July
Winter low6 °Faverage low, January
Hot days5days a year at 90 °F or more
Freezing nights180nights a year at 32 °F or less
Growing degree days1,929base 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)
Precipitation47.2 inper year, rain and melted snow
Snowfall91 inper year; 107 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 6 °F 28°6° JanFebruary: average high 31 °F, low 6 °F 31°6° FebMarch: average high 39 °F, low 17 °F 39°17° MarApril: average high 53 °F, low 30 °F 53°30° AprMay: average high 66 °F, low 41 °F 66°41° MayJune: average high 74 °F, low 50 °F 74°50° JunJuly: average high 80 °F, low 57 °F 80°57° JulAugust: average high 79 °F, low 54 °F 79°54° AugSeptember: average high 71 °F, low 45 °F 71°45° SepOctober: average high 58 °F, low 35 °F 58°35° OctNovember: average high 45 °F, low 24 °F 45°24° NovDecember: average high 34 °F, low 15 °F 34°15° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″6″January: 3.36 in precipitation, 19.8 in snowfall 3.4❄20 JanFebruary: 3.05 in precipitation, 26.6 in snowfall 3.0❄27 FebMarch: 3.69 in precipitation, 15.9 in snowfall 3.7❄16 MarApril: 4.06 in precipitation, 3.2 in snowfall 4.1❄3 AprMay: 3.42 in precipitation, 0.3 in snowfall 3.4 MayJune: 4.48 in precipitation 4.5 JunJuly: 3.93 in precipitation 3.9 JulAugust: 3.78 in precipitation 3.8 AugSeptember: 3.50 in precipitation 3.5 SepOctober: 5.18 in precipitation, 0.4 in snowfall 5.2 OctNovember: 4.29 in precipitation, 4.7 in snowfall 4.3❄5 NovDecember: 4.42 in precipitation, 20.3 in snowfall 4.4❄20 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Livermore Falls 1 E, ME (4 mi away); precipitation: Livermore Falls 1 E, ME (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

042625a
North Jay, ME · 3 mi
042215a
Canton, ME · 5 mi
042275a
East Dixfield, ME · 6 mi
042545b
Livermore Falls, ME · 6 mi
042254b
Dryden, ME · 6 mi
042345a
East Wilton, ME · 7 mi
042535b
Livermore, ME · 7 mi
043495b
Kents Hill, ME · 9 mi

Maine planting zones →

Questions about 04239

What planting zone is ZIP code 04239?

ZIP code 04239 (Jay, ME) 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 Jay, ME?

The median last spring frost (32 °F) near 04239 is May 11; after May 24 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Livermore Falls 1 E station.

When is the first frost in Jay, ME?

The median first fall frost near 04239 is September 29, giving a median frost-free growing season of 138 days.

When should I plant tomatoes in 04239?

Start tomato seeds indoors around Mar 16 – Mar 30 and set transplants outside around May 18 – Jun 1, one to three weeks after the median last frost.

How much rain and snow does 04239 get?

About 47.2 inches of precipitation a year and 91 inches of snowfall (NOAA 1991–2020 normals, Livermore Falls 1 E station).

How hot do summers get in Jay, ME?

The average high peaks at 80 °F in July, with about 5 days a year at 90 °F or more.

What kind of soil does 04239 have?

The USDA soil survey maps Colonel at the center of ZIP 04239: highly decomposed plant material, somewhat poorly drained, pH about 5.0 (strongly acidic).

Did spring come early in Jay, ME in 2026?

Spring leaf-out near 04239 came on Apr 17 in 2026, 7 days earlier than the 1991–2020 average (Apr 24), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Jay, ME?

Long-day onions: the longest day near 04239 is 15 h 33 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 04239 change?

Yes. The 2012 USDA map put 04239 in zone 4b; the 2023 map puts it in zone 5a. The newer map uses 1991–2020 data and more weather stations.