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

Planting zone for 06754 — Cornwall Bridge, CT

ZIP code 06754 (Cornwall Bridge, Northwest Hills County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 11 and the first fall frost October 4.

Where ZIP 06754 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.

Zone6a−10 to −5 °F
Coldest night−23.3 to −20.6 °C
Last frostMay 11
First frostOct 4
2012 zone6a

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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Cornwall Bridge, 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 Cornwall Bridge, CT

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 27only 10% chance of frost after
First fall frostOctober 4median — 10% chance by Sep 21
Growing season146 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 30 and returns around October 15.

From the NOAA station Falls Village, CT — 14 miles away, elevation 551 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 06754

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 9 – Aug 23
GarlicPlant cloves · Sep 20 – Oct 25
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 11) and first fall frost (Oct 4) 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 06754 came on Apr 9 — 4 days earlier than the 1991–2020 average (Apr 13).

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 6a in Connecticut

528 plants native to the lower 48 states, recorded in Connecticut, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. 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 185

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 149

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 °Fbeaked spikerush3 ft · blooms late spring · high shade tolerance · to −28 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °F

Vines 8

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 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °Ftrumpet creeper2 ft · blooms summer · high shade tolerance · to −13 °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 Cornwall Bridge, CT.

Soil in Cornwall Bridge, CT

The soil mapped at the center of ZIP 06754 is Catden — muck, very poorly drained.

TextureMucktop layer
DrainageVery poorly drainedconsider raised beds
Organic matter82%high
Hydrologic groupB/Dmoderate when drained; wet otherwise
Farmland classNot prime farmlandUSDA classification

Map unit: Catden and Freetown soils, 0 to 2 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 06754; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Cornwall Bridge, CT

Summer high85 °Faverage high, July
Winter low14 °Faverage low, January
Hot days12days a year at 90 °F or more
Freezing nights156nights a year at 32 °F or less
Growing degree days2,576base 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)
Precipitation51.7 inper year, rain and melted snow

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 35 °F, low 14 °F 35°14° JanFebruary: average high 39 °F, low 15 °F 39°15° FebMarch: average high 47 °F, low 23 °F 47°23° MarApril: average high 60 °F, low 33 °F 60°33° AprMay: average high 72 °F, low 44 °F 72°44° MayJune: average high 80 °F, low 53 °F 80°53° JunJuly: average high 85 °F, low 58 °F 85°58° JulAugust: average high 82 °F, low 57 °F 82°57° AugSeptember: average high 76 °F, low 49 °F 76°49° SepOctober: average high 63 °F, low 38 °F 63°38° OctNovember: average high 51 °F, low 29 °F 51°29° NovDecember: average high 40 °F, low 20 °F 40°20° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 3.61 in precipitation 3.6 JanFebruary: 3.11 in precipitation 3.1 FebMarch: 4.07 in precipitation 4.1 MarApril: 3.82 in precipitation 3.8 AprMay: 4.01 in precipitation 4.0 MayJune: 4.47 in precipitation 4.5 JunJuly: 4.26 in precipitation 4.3 JulAugust: 5.30 in precipitation 5.3 AugSeptember: 5.51 in precipitation 5.5 SepOctober: 4.90 in precipitation 4.9 OctNovember: 3.80 in precipitation 3.8 NovDecember: 4.87 in precipitation 4.9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Falls Village, CT (14 mi away); precipitation: Warren 2.4 Wnw, CT (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

067776a
New Preston Marble Dale, CT · 5 mi
067536a
Cornwall, CT · 5 mi
067576a
Kent, CT · 5 mi
067856a
South Kent, CT · 5 mi
067506a
Bantam, CT · 6 mi
067946a
Washington Depot, CT · 8 mi
067596a
Litchfield, CT · 8 mi
067966a
West Cornwall, CT · 8 mi

Connecticut planting zones →

Questions about 06754

What planting zone is ZIP code 06754?

ZIP code 06754 (Cornwall Bridge, CT) is in USDA hardiness zone 6a on the 2023 map: the coldest night of an average winter reaches −10 to −5 °F (−23.3 to −20.6 °C).

When is the last frost in Cornwall Bridge, CT?

The median last spring frost (32 °F) near 06754 is May 11; after May 27 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Falls Village station.

When is the first frost in Cornwall Bridge, CT?

The median first fall frost near 06754 is October 4, giving a median frost-free growing season of 146 days.

When should I plant tomatoes in 06754?

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 06754 get?

About 51.7 inches of precipitation a year (NOAA 1991–2020 normals, Warren 2.4 Wnw station).

How hot do summers get in Cornwall Bridge, CT?

The average high peaks at 85 °F in July, with about 12 days a year at 90 °F or more.

What kind of soil does 06754 have?

The USDA soil survey maps Catden at the center of ZIP 06754: muck, very poorly drained.

Did spring come early in Cornwall Bridge, CT in 2026?

Spring leaf-out near 06754 came on Apr 9 in 2026, 4 days earlier than the 1991–2020 average (Apr 13), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Cornwall Bridge, CT?

Long-day onions: the longest day near 06754 is 15 h 13 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).