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

Planting zone for 62236 — Columbia, IL

ZIP code 62236 (Columbia, Monroe County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 6 and the first fall frost October 27.

Where ZIP 62236 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.

Zone7a0 to 5 °F

Coldest night−17.8 to −15 °C

Last frostApr 6

First frostOct 27

2012 zone6b

Was 6b 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 7a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Columbia, 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 Columbia, IL

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 6median — 50% chance of a later frost

Safe for tender plantsApril 20only 10% chance of frost after

First fall frostOctober 27median — 10% chance by Oct 14

Growing season203 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 27 and returns around November 5.

From the NOAA station Cahokia, IL — 9 miles away, elevation 400 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 62236

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 23 – Mar 9

SpinachSow outdoors · Feb 23 – Mar 16

Broccoli, cabbageStart indoors · Jan 26 – Feb 9

Broccoli, cabbageTransplant · Mar 16 – Mar 30

Onion setsPlant outdoors · Mar 9 – Mar 23

PotatoesPlant outdoors · Mar 16 – Mar 30

LettuceSow outdoors · Mar 9 – Mar 23

Carrots, beetsSow outdoors · Mar 16 – Mar 30

TomatoesStart indoors · Feb 9 – Feb 23

TomatoesTransplant · Apr 13 – Apr 27

Peppers, eggplantStart indoors · Jan 26 – Feb 9

Peppers, eggplantTransplant · Apr 20 – May 4

BeansSow outdoors · Apr 13 – Apr 27

Sweet cornSow outdoors · Apr 13 – Apr 27

Cucumbers, squashSow outdoors · Apr 13 – Apr 27

Fall lettuce, spinachSow outdoors · Sep 1 – Sep 15

GarlicPlant cloves · Oct 13 – Nov 17

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 6) and first fall frost (Oct 27) 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 62236 came on Mar 3 — 10 days earlier than the 1991–2020 average (Mar 13).

average
Mar 132026
Mar 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).

Native plants for zone 7a in Illinois

633 plants native to the lower 48 states, recorded in Illinois, and rated by the USDA to survive 0 °F or colder — the bottom of zone 7a. 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 Columbia, IL.

Soil in Columbia, IL

The soil mapped at the center of ZIP 62236 is Wakeland — silt loam, somewhat poorly drained.

TextureSilt loama good balance for most vegetables

pH6.5neutral; most vegetables like 6.0–7.0

DrainageSomewhat poorly drainedconsider raised beds

Organic matter2%moderate

Hydrologic groupB/Dmoderate when drained; wet otherwise

Farmland classPrime farmland if drained and either protected from flooding or not frequently flooded during the growing seasonUSDA classification

Map unit: Wakeland silt loam, 0 to 2 percent slopes, frequently flooded.

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 62236; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Columbia, IL

Summer high89 °Faverage high, July

Winter low22 °Faverage low, January

Hot days39days a year at 90 °F or more

Freezing nights97nights a year at 32 °F or less

Growing degree days4,249base 50 °F — the season’s usable heat

Longest day14 h 51 mindaylight on June 21

Shortest day9 h 29 mindaylight on December 21

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

Precipitation45.1 inper year, rain and melted snow

Snowfall9 inper year

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Cahokia, IL (9 mi away); precipitation: Waterloo, IL (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

622407a

East Carondelet, IL · 5 mi

631297a

Saint Louis, MO · 6 mi

Saint Louis, MO · 7 mi

631117a

Saint Louis, MO · 9 mi

Illinois planting zones →

Questions about 62236

What planting zone is ZIP code 62236?

ZIP code 62236 (Columbia, IL) is in USDA hardiness zone 7a on the 2023 map: the coldest night of an average winter reaches 0 to 5 °F (−17.8 to −15 °C).

When is the last frost in Columbia, IL?

The median last spring frost (32 °F) near 62236 is April 6; after April 20 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Cahokia station.

When is the first frost in Columbia, IL?

The median first fall frost near 62236 is October 27, giving a median frost-free growing season of 203 days.

When should I plant tomatoes in 62236?

Start tomato seeds indoors around Feb 9 – Feb 23 and set transplants outside around Apr 13 – Apr 27, one to three weeks after the median last frost.

How much rain and snow does 62236 get?

About 45.1 inches of precipitation a year and 9 inches of snowfall (NOAA 1991–2020 normals, Waterloo station).

How hot do summers get in Columbia, IL?

The average high peaks at 89 °F in July, with about 39 days a year at 90 °F or more.

What kind of soil does 62236 have?

The USDA soil survey maps Wakeland at the center of ZIP 62236: silt loam, somewhat poorly drained, pH about 6.5 (neutral).

Did spring come early in Columbia, IL in 2026?

Spring leaf-out near 62236 came on Mar 3 in 2026, 10 days earlier than the 1991–2020 average (Mar 13), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Columbia, IL?

Intermediate onions: the longest day near 62236 is 14 h 51 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 62236 change?

Yes. The 2012 USDA map put 62236 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.