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

Planting zone for 62010 — Bethalto, IL

ZIP code 62010 (Bethalto, Madison County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 4 and the first fall frost November 5.

Where ZIP 62010 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.

Zone6b−5 to 0 °F

Coldest night−20.6 to −17.8 °C

Last frostApr 4

First frostNov 5

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 Bethalto, IL…

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 Bethalto, IL

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostApril 4median — 50% chance of a later frost

Safe for tender plantsApril 19only 10% chance of frost after

First fall frostNovember 5median — 10% chance by Oct 25

Growing season214 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 25 and returns around November 16.

From the NOAA station Alton - Melvin Price L&D, IL — 6 miles away, elevation 404 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 62010

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 21 – Mar 7

SpinachSow outdoors · Feb 21 – Mar 14

Broccoli, cabbageStart indoors · Jan 24 – Feb 7

Broccoli, cabbageTransplant · Mar 14 – Mar 28

Onion setsPlant outdoors · Mar 7 – Mar 21

PotatoesPlant outdoors · Mar 14 – Mar 28

LettuceSow outdoors · Mar 7 – Mar 21

Carrots, beetsSow outdoors · Mar 14 – Mar 28

TomatoesStart indoors · Feb 7 – Feb 21

TomatoesTransplant · Apr 11 – Apr 25

Peppers, eggplantStart indoors · Jan 24 – Feb 7

Peppers, eggplantTransplant · Apr 18 – May 2

BeansSow outdoors · Apr 11 – Apr 25

Sweet cornSow outdoors · Apr 11 – Apr 25

Cucumbers, squashSow outdoors · Apr 11 – Apr 25

Fall lettuce, spinachSow outdoors · Sep 10 – Sep 24

GarlicPlant cloves · Oct 22 – Nov 26

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 4) and first fall frost (Nov 5) 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 62010 came on Mar 6 — 11 days earlier than the 1991–2020 average (Mar 17).

average
Mar 172026
Mar 6

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 Illinois

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

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 Bethalto, IL.

Soil in Bethalto, IL

The soil mapped at the center of ZIP 62010 is Ruma — silt loam, well drained.

TextureSilt loama good balance for most vegetables

pH6.5neutral; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter2%moderate

Hydrologic groupBwater soaks in moderately

Farmland classNot prime farmlandUSDA classification

Map unit: Ruma-Hickory silt loams, 18 to 35 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 62010; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Bethalto, IL

Summer high87 °Faverage high, July

Winter low22 °Faverage low, January

Hot days29days a year at 90 °F or more

Freezing nights85nights a year at 32 °F or less

Growing degree days4,168base 50 °F — the season’s usable heat

Longest day14 h 54 mindaylight on June 21

Shortest day9 h 26 mindaylight on December 21

Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully

Precipitation41.9 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: Alton - Melvin Price L&D, IL (6 mi away); precipitation: Alton - Melvin Price L&D, IL (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

620187a

Cottage Hills, IL · 2 mi

620247a

East Alton, IL · 3 mi

620676b

Moro, IL · 4 mi

620957a

Wood River, IL · 4 mi

South Roxana, IL · 7 mi

Illinois planting zones →

Questions about 62010

What planting zone is ZIP code 62010?

ZIP code 62010 (Bethalto, IL) 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 Bethalto, IL?

The median last spring frost (32 °F) near 62010 is April 4; after April 19 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Alton - Melvin Price L&D station.

When is the first frost in Bethalto, IL?

The median first fall frost near 62010 is November 5, giving a median frost-free growing season of 214 days.

When should I plant tomatoes in 62010?

Start tomato seeds indoors around Feb 7 – Feb 21 and set transplants outside around Apr 11 – Apr 25, one to three weeks after the median last frost.

How much rain and snow does 62010 get?

About 41.9 inches of precipitation a year (NOAA 1991–2020 normals, Alton - Melvin Price L&D station).

How hot do summers get in Bethalto, IL?

The average high peaks at 87 °F in July, with about 29 days a year at 90 °F or more.

What kind of soil does 62010 have?

The USDA soil survey maps Ruma at the center of ZIP 62010: silt loam, well drained, pH about 6.5 (neutral).

Did spring come early in Bethalto, IL in 2026?

Spring leaf-out near 62010 came on Mar 6 in 2026, 11 days earlier than the 1991–2020 average (Mar 17), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Bethalto, IL?

Intermediate onions: the longest day near 62010 is 14 h 54 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 62010 change?

Yes. The 2012 USDA map put 62010 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.