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

Planting zone for 62353 — Mount Sterling, IL

ZIP code 62353 (Mount Sterling, Brown County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 18 and the first fall frost October 15.

Where ZIP 62353 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 frostApr 18
First frostOct 15
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 Mount Sterling, 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 Mount Sterling, IL

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 18median — 50% chance of a later frost
Safe for tender plantsMay 5only 10% chance of frost after
First fall frostOctober 15median — 10% chance by Sep 30
Growing season179 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 6 and returns around October 27.

From the NOAA station Perry 6 Nw, IL — 12 miles away, elevation 650 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 62353

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 7 – Mar 21
SpinachSow outdoors · Mar 7 – Mar 28
Broccoli, cabbageStart indoors · Feb 7 – Feb 21
Broccoli, cabbageTransplant · Mar 28 – Apr 11
Onion setsPlant outdoors · Mar 21 – Apr 4
PotatoesPlant outdoors · Mar 28 – Apr 11
LettuceSow outdoors · Mar 21 – Apr 4
Carrots, beetsSow outdoors · Mar 28 – Apr 11
TomatoesStart indoors · Feb 21 – Mar 7
TomatoesTransplant · Apr 25 – May 9
Peppers, eggplantStart indoors · Feb 7 – Feb 21
Peppers, eggplantTransplant · May 2 – May 16
BeansSow outdoors · Apr 25 – May 9
Sweet cornSow outdoors · Apr 25 – May 9
Cucumbers, squashSow outdoors · Apr 25 – May 9
Fall lettuce, spinachSow outdoors · Aug 20 – Sep 3
GarlicPlant cloves · Oct 1 – Nov 5
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 18) and first fall frost (Oct 15) 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 62353 came on Mar 10 — 16 days earlier than the 1991–2020 average (Mar 26).

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 Illinois

610 plants native to the lower 48 states, recorded in Illinois, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. Each links to its USDA PLANTS profile.

Trees 78

Shrubs 108

Wildflowers & perennials 220

Grasses 178

Vines 9

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 Mount Sterling, IL.

Soil in Mount Sterling, IL

The soil mapped at the center of ZIP 62353 is Clarksdale — silt loam, somewhat poorly drained.

TextureSilt loama good balance for most vegetables
pH6.6neutral; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter2.5%moderate
Hydrologic groupC/Dslow when drained; wet otherwise
Farmland classPrime farmland if drainedUSDA classification

Map unit: Clarksdale silt loam, 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 62353; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mount Sterling, IL

Summer high87 °Faverage high, July
Winter low18 °Faverage low, January
Hot days31days a year at 90 °F or more
Freezing nights126nights a year at 32 °F or less
Growing degree days3,727base 50 °F — the season’s usable heat
Longest day15 h 01 mindaylight on June 21
Shortest day9 h 20 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation39.4 inper year, rain and melted snow
Snowfall14 inper year; 24 days with snow on the ground

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 37 °F, low 18 °F 37°18° JanFebruary: average high 42 °F, low 22 °F 42°22° FebMarch: average high 53 °F, low 31 °F 53°31° MarApril: average high 65 °F, low 42 °F 65°42° AprMay: average high 75 °F, low 53 °F 75°53° MayJune: average high 84 °F, low 62 °F 84°62° JunJuly: average high 87 °F, low 65 °F 87°65° JulAugust: average high 86 °F, low 63 °F 86°63° AugSeptember: average high 80 °F, low 54 °F 80°54° SepOctober: average high 68 °F, low 43 °F 68°43° OctNovember: average high 53 °F, low 33 °F 53°33° NovDecember: average high 41 °F, low 23 °F 41°23° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 1.78 in precipitation, 5.3 in snowfall 1.8❄5 JanFebruary: 1.94 in precipitation, 2.8 in snowfall 1.9❄3 FebMarch: 2.67 in precipitation, 1.3 in snowfall 2.7❄1 MarApril: 4.17 in precipitation 4.2 AprMay: 4.99 in precipitation 5.0 MayJune: 4.59 in precipitation 4.6 JunJuly: 3.45 in precipitation 3.5 JulAugust: 3.80 in precipitation 3.8 AugSeptember: 3.54 in precipitation 3.5 SepOctober: 3.40 in precipitation 3.4 OctNovember: 2.63 in precipitation, 0.6 in snowfall 2.6❄1 NovDecember: 2.42 in precipitation, 3.5 in snowfall 2.4❄4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Perry 6 Nw, IL (12 mi away); precipitation: Mt Sterling, IL (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

Illinois planting zones →

Questions about 62353

What planting zone is ZIP code 62353?

ZIP code 62353 (Mount Sterling, IL) 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 Mount Sterling, IL?

The median last spring frost (32 °F) near 62353 is April 18; after May 5 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Perry 6 Nw station.

When is the first frost in Mount Sterling, IL?

The median first fall frost near 62353 is October 15, giving a median frost-free growing season of 179 days.

When should I plant tomatoes in 62353?

Start tomato seeds indoors around Feb 21 – Mar 7 and set transplants outside around Apr 25 – May 9, one to three weeks after the median last frost.

How much rain and snow does 62353 get?

About 39.4 inches of precipitation a year and 14 inches of snowfall (NOAA 1991–2020 normals, Mt Sterling station).

How hot do summers get in Mount Sterling, IL?

The average high peaks at 87 °F in July, with about 31 days a year at 90 °F or more.

What kind of soil does 62353 have?

The USDA soil survey maps Clarksdale at the center of ZIP 62353: silt loam, somewhat poorly drained, pH about 6.6 (neutral).

Did spring come early in Mount Sterling, IL in 2026?

Spring leaf-out near 62353 came on Mar 10 in 2026, 16 days earlier than the 1991–2020 average (Mar 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mount Sterling, IL?

Long-day onions: the longest day near 62353 is 15 h 01 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 62353 change?

Yes. The 2012 USDA map put 62353 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.