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

Planting zone for 06265 — South Willington, CT

ZIP code 06265 (South Willington, Capitol Region County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 19 and the first fall frost October 22.

Where ZIP 06265 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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostApr 19
First frostOct 22
2012 zone6a

Was 6a 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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for South Willington, CT…

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 South Willington, CT

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 19median — 50% chance of a later frost
Safe for tender plantsMay 3only 10% chance of frost after
First fall frostOctober 22median — 10% chance by Oct 6
Growing season186 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 6 and returns around November 4.

From the NOAA station Storrs, CT — 6 miles away, elevation 666 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 06265

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 8 – Mar 22
SpinachSow outdoors · Mar 8 – Mar 29
Broccoli, cabbageStart indoors · Feb 8 – Feb 22
Broccoli, cabbageTransplant · Mar 29 – Apr 12
Onion setsPlant outdoors · Mar 22 – Apr 5
PotatoesPlant outdoors · Mar 29 – Apr 12
LettuceSow outdoors · Mar 22 – Apr 5
Carrots, beetsSow outdoors · Mar 29 – Apr 12
TomatoesStart indoors · Feb 22 – Mar 8
TomatoesTransplant · Apr 26 – May 10
Peppers, eggplantStart indoors · Feb 8 – Feb 22
Peppers, eggplantTransplant · May 3 – May 17
BeansSow outdoors · Apr 26 – May 10
Sweet cornSow outdoors · Apr 26 – May 10
Cucumbers, squashSow outdoors · Apr 26 – May 10
Fall lettuce, spinachSow outdoors · Aug 27 – Sep 10
GarlicPlant cloves · Oct 8 – Nov 12
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 19) and first fall frost (Oct 22) 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 06265 came on Apr 3 — 8 days earlier than the 1991–2020 average (Apr 11).

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 6b in Connecticut

533 plants native to the lower 48 states, recorded in Connecticut, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. Each links to its USDA PLANTS profile.

Trees 64

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 105

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 holly40 ft · blooms mid spring · low shade tolerance · to −20 °F

Wildflowers & perennials 187

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican licorice4 ft · blooms late spring · medium shade tolerance · to −38 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °F

Grasses 151

American beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °Farctic brome3 ft · blooms early summer · low shade tolerance · to −33 °FAtlantic mannagrass3 ft · blooms summer · low shade tolerance · to −8 °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 9

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fcatbird grape30 ft · blooms late spring · medium shade tolerance · to −13 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Fheartleaf peppervine2 ft · blooms late spring · low shade tolerance · to −8 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °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 South Willington, CT.

Soil in South Willington, CT

The soil mapped at the center of ZIP 06265 is Udorthents — loam, well drained.

TextureLoama good balance for most vegetables
pH5.6moderately acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter4%moderate
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Udorthents-Urban land complex.

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 06265; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in South Willington, CT

Summer high81 °Faverage high, July
Winter low19 °Faverage low, January
Hot days3days a year at 90 °F or more
Freezing nights123nights a year at 32 °F or less
Growing degree days2,683base 50 °F — the season’s usable heat
Longest day15 h 13 mindaylight on June 21
Shortest day9 h 08 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation52.4 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 35 °F, low 19 °F 35°19° JanFebruary: average high 37 °F, low 20 °F 37°20° FebMarch: average high 45 °F, low 28 °F 45°28° MarApril: average high 57 °F, low 38 °F 57°38° AprMay: average high 68 °F, low 48 °F 68°48° MayJune: average high 76 °F, low 57 °F 76°57° JunJuly: average high 81 °F, low 63 °F 81°63° JulAugust: average high 79 °F, low 61 °F 79°61° AugSeptember: average high 73 °F, low 54 °F 73°54° SepOctober: average high 61 °F, low 43 °F 61°43° OctNovember: average high 50 °F, low 34 °F 50°34° NovDecember: average high 40 °F, low 25 °F 40°25° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 4.05 in precipitation 4.0 JanFebruary: 3.33 in precipitation 3.3 FebMarch: 4.80 in precipitation 4.8 MarApril: 4.14 in precipitation 4.1 AprMay: 3.56 in precipitation 3.6 MayJune: 4.16 in precipitation 4.2 JunJuly: 5.69 in precipitation 5.7 JulAugust: 4.67 in precipitation 4.7 AugSeptember: 4.39 in precipitation 4.4 SepOctober: 4.73 in precipitation 4.7 OctNovember: 3.95 in precipitation 4.0 NovDecember: 4.88 in precipitation 4.9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Storrs, CT (6 mi away); precipitation: Willington 2.7 Se, CT (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

060846b
Tolland, CT · 4 mi
062796b
Willington, CT · 4 mi
062516b
Mansfield Depot, CT · 4 mi
062696b
Storrs Mansfield, CT · 4 mi
062686b
Storrs Mansfield, CT · 5 mi
062386b
Coventry, CT · 6 mi
062786b
Ashford, CT · 7 mi
062506b
Mansfield Center, CT · 8 mi

Connecticut planting zones →

Questions about 06265

What planting zone is ZIP code 06265?

ZIP code 06265 (South Willington, CT) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in South Willington, CT?

The median last spring frost (32 °F) near 06265 is April 19; after May 3 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Storrs station.

When is the first frost in South Willington, CT?

The median first fall frost near 06265 is October 22, giving a median frost-free growing season of 186 days.

When should I plant tomatoes in 06265?

Start tomato seeds indoors around Feb 22 – Mar 8 and set transplants outside around Apr 26 – May 10, one to three weeks after the median last frost.

How much rain and snow does 06265 get?

About 52.4 inches of precipitation a year (NOAA 1991–2020 normals, Willington 2.7 Se station).

How hot do summers get in South Willington, CT?

The average high peaks at 81 °F in July, with about 3 days a year at 90 °F or more.

What kind of soil does 06265 have?

The USDA soil survey maps Udorthents at the center of ZIP 06265: loam, well drained, pH about 5.6 (moderately acidic).

Did spring come early in South Willington, CT in 2026?

Spring leaf-out near 06265 came on Apr 3 in 2026, 8 days earlier than the 1991–2020 average (Apr 11), according to the USA National Phenology Network Spring Index.

What kind of onions grow in South Willington, CT?

Long-day onions: the longest day near 06265 is 15 h 13 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 06265 change?

Yes. The 2012 USDA map put 06265 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.