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

Planting zone for Waterville, ME

Waterville, ME is in USDA zone 5b across its 2 ZIP codes. The median last spring frost is May 2 and the first fall frost October 10.

Waterville on the zone map

Outlined: its 1 ZIP code areas · 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.

Zone5b−15 to −10 °F
ZIP codes2
Last frostMay 2
First frostOct 10
Growing season159 days

5b 2 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

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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 Waterville, ME

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 2median — 50% chance of a later frost
Safe for tender plantsMay 14only 10% chance of frost after
First fall frostOctober 10median — 10% chance by Sep 30
Growing season159 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 22 and returns around October 24.

From the NOAA station Waterville Trtmt Plt, ME, elevation 72 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 Waterville

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 21 – Apr 4
SpinachSow outdoors · Mar 21 – Apr 11
Broccoli, cabbageStart indoors · Feb 21 – Mar 7
Broccoli, cabbageTransplant · Apr 11 – Apr 25
Onion setsPlant outdoors · Apr 4 – Apr 18
PotatoesPlant outdoors · Apr 11 – Apr 25
LettuceSow outdoors · Apr 4 – Apr 18
Carrots, beetsSow outdoors · Apr 11 – Apr 25
TomatoesStart indoors · Mar 7 – Mar 21
TomatoesTransplant · May 9 – May 23
Peppers, eggplantStart indoors · Feb 21 – Mar 7
Peppers, eggplantTransplant · May 16 – May 30
BeansSow outdoors · May 9 – May 23
Sweet cornSow outdoors · May 9 – May 23
Cucumbers, squashSow outdoors · May 9 – May 23
Fall lettuce, spinachSow outdoors · Aug 15 – Aug 29
GarlicPlant cloves · Sep 26 – Oct 31
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 2) and first fall frost (Oct 10) 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 04903 came on Apr 16 — 7 days earlier than the 1991–2020 average (Apr 23).

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 5b in Maine

493 plants native to the lower 48 states, recorded in Maine, and rated by the USDA to survive −15 °F or colder — the bottom of zone 5b. Each links to its USDA PLANTS profile.

Trees 55

Shrubs 98

Wildflowers & perennials 169

Grasses 153

Vines 6

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 Waterville, ME.

Soil in Waterville, ME

The soil mapped at the center of ZIP 04903 is Peru — fine sandy loam, moderately well drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding
pH5.0strongly acidic; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter7%high
Hydrologic groupC/Dslow when drained; wet otherwise
Farmland classprime farmlandUSDA classification

Map unit: Peru fine sandy loam, 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 04903; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Waterville, ME

Summer high80 °Faverage high, July
Winter low9 °Faverage low, January
Hot days6days a year at 90 °F or more
Freezing nights164nights a year at 32 °F or less
Growing degree days2,201base 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)
Precipitation43.4 inper year, rain and melted snow

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 29 °F, low 9 °F 29°9° JanFebruary: average high 32 °F, low 10 °F 32°10° FebMarch: average high 40 °F, low 21 °F 40°21° MarApril: average high 54 °F, low 32 °F 54°32° AprMay: average high 66 °F, low 43 °F 66°43° MayJune: average high 75 °F, low 53 °F 75°53° JunJuly: average high 80 °F, low 59 °F 80°59° JulAugust: average high 80 °F, low 57 °F 80°57° AugSeptember: average high 72 °F, low 50 °F 72°50° SepOctober: average high 59 °F, low 38 °F 59°38° OctNovember: average high 46 °F, low 29 °F 46°29° NovDecember: average high 35 °F, low 17 °F 35°17° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 3.12 in precipitation 3.1 JanFebruary: 2.61 in precipitation 2.6 FebMarch: 3.27 in precipitation 3.3 MarApril: 3.73 in precipitation 3.7 AprMay: 3.33 in precipitation 3.3 MayJune: 4.03 in precipitation 4.0 JunJuly: 3.37 in precipitation 3.4 JulAugust: 3.39 in precipitation 3.4 AugSeptember: 3.82 in precipitation 3.8 SepOctober: 4.90 in precipitation 4.9 OctNovember: 3.87 in precipitation 3.9 NovDecember: 3.92 in precipitation 3.9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Waterville Trtmt Plt, ME (3 mi away); precipitation: Waterville Trtmt Plt, ME (3 mi away). Daylight is calculated from latitude.

ZIP codes in Waterville

Maine planting zones →

Questions about Waterville

What planting zone is Waterville, ME?

Waterville, ME is in USDA hardiness zone 5b on the 2023 map (5b: −15 to −10 °F).

When is the last frost in Waterville, ME?

The median last spring frost is May 2 and the median first fall frost is October 10 (NOAA 1991–2020 normals, Waterville Trtmt Plt station).

When can I plant a garden in Waterville, ME?

Cool-season crops like peas and spinach go in around Mar 21 – Apr 11; tomatoes, peppers, beans and squash after about May 9, once frost risk has passed.

What kind of onions grow in Waterville, ME?

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

How much rain and snow does Waterville, ME get?

About 43.4 inches of precipitation a year (NOAA 1991–2020 normals).