Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 06039 — Lakeville, CT

ZIP code 06039 (Lakeville, 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 06039 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 zone5b

Was 5b 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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Lakeville, 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 Lakeville, 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 — 4 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 06039

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 06039 came on Apr 3 — 10 days earlier than the 1991–2020 average (Apr 13).

average
Apr 132026
Apr 3

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).

Soil in Lakeville, CT

The soil mapped at the center of ZIP 06039 is Bernardston — silt loam, well drained.

TextureSilt loama good balance for most vegetables

pH5.3strongly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter3.5%moderate

Hydrologic groupCwater soaks in slowly

Farmland classprime farmlandUSDA classification

Map unit: Bernardston silt 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 06039; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Lakeville, 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 14 mindaylight on June 21

Shortest day9 h 07 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation46.9 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

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

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

Falls Village, CT · 7 mi

060696a

Sharon, CT · 7 mi

067966a

West Cornwall, CT · 8 mi

060186a

Canaan, CT · 9 mi

125036a

Ancramdale, NY · 9 mi

Connecticut planting zones →

Questions about 06039

What planting zone is ZIP code 06039?

ZIP code 06039 (Lakeville, 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 Lakeville, CT?

The median last spring frost (32 °F) near 06039 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 Lakeville, CT?

The median first fall frost near 06039 is October 4, giving a median frost-free growing season of 146 days.

When should I plant tomatoes in 06039?

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 06039 get?

About 46.9 inches of precipitation a year (NOAA 1991–2020 normals, Falls Village station).

How hot do summers get in Lakeville, 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 06039 have?

The USDA soil survey maps Bernardston at the center of ZIP 06039: silt loam, well drained, pH about 5.3 (strongly acidic).

Did spring come early in Lakeville, CT in 2026?

Spring leaf-out near 06039 came on Apr 3 in 2026, 10 days earlier than the 1991–2020 average (Apr 13), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Lakeville, CT?

Long-day onions: the longest day near 06039 is 15 h 14 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 06039 change?

Yes. The 2012 USDA map put 06039 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.