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

Planting zone for 62286 — Sparta, IL

ZIP code 62286 (Sparta, Randolph County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 12 and the first fall frost October 22.

Where ZIP 62286 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 12

First frostOct 22

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 Sparta, 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 Sparta, IL

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 12median — 50% chance of a later frost

Safe for tender plantsApril 29only 10% chance of frost after

First fall frostOctober 22median — 10% chance by Oct 7

Growing season191 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 1 and returns around November 1.

From the NOAA station Sparta 1 W, IL — within 1 mile, elevation 535 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 62286

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 1 – Mar 15

SpinachSow outdoors · Mar 1 – Mar 22

Broccoli, cabbageStart indoors · Feb 1 – Feb 15

Broccoli, cabbageTransplant · Mar 22 – Apr 5

Onion setsPlant outdoors · Mar 15 – Mar 29

PotatoesPlant outdoors · Mar 22 – Apr 5

LettuceSow outdoors · Mar 15 – Mar 29

Carrots, beetsSow outdoors · Mar 22 – Apr 5

TomatoesStart indoors · Feb 15 – Mar 1

TomatoesTransplant · Apr 19 – May 3

Peppers, eggplantStart indoors · Feb 1 – Feb 15

Peppers, eggplantTransplant · Apr 26 – May 10

BeansSow outdoors · Apr 19 – May 3

Sweet cornSow outdoors · Apr 19 – May 3

Cucumbers, squashSow outdoors · Apr 19 – May 3

Fall lettuce, spinachSow outdoors · Aug 27 – Sep 10

GarlicPlant cloves · Oct 8 – Nov 12

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 12) and first fall frost (Oct 22) 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 62286 came on Mar 2 — 11 days earlier than the 1991–2020 average (Mar 13).

average
Mar 132026
Mar 2

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 Sparta, IL.

Soil in Sparta, IL

The soil mapped at the center of ZIP 62286 is Homen — silt loam, moderately well drained.

TextureSilt loama good balance for most vegetables

pH6.5neutral; most vegetables like 6.0–7.0

DrainageModerately well drainednatural drainage class

Organic matter1.5%low — add compost

Hydrologic groupCwater soaks in slowly

Farmland classFarmland of statewide importanceUSDA classification

Map unit: Homen silt loam, 5 to 10 percent slopes, eroded.

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 62286; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Sparta, IL

Summer high88 °Faverage high, July

Winter low22 °Faverage low, January

Hot days35days a year at 90 °F or more

Freezing nights109nights a year at 32 °F or less

Growing degree days3,944base 50 °F — the season’s usable heat

Longest day14 h 49 mindaylight on June 21

Shortest day9 h 31 mindaylight on December 21

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

Precipitation45.6 inper year, rain and melted snow

Snowfall11 inper year

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Sparta 1 W, IL (within 1 mile); precipitation: Sparta 1 W, IL (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

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

Steeleville, IL · 9 mi

622376b

Coulterville, IL · 10 mi

Willisville, IL · 12 mi

Illinois planting zones →

Questions about 62286

What planting zone is ZIP code 62286?

ZIP code 62286 (Sparta, 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 Sparta, IL?

The median last spring frost (32 °F) near 62286 is April 12; after April 29 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Sparta 1 W station.

When is the first frost in Sparta, IL?

The median first fall frost near 62286 is October 22, giving a median frost-free growing season of 191 days.

When should I plant tomatoes in 62286?

Start tomato seeds indoors around Feb 15 – Mar 1 and set transplants outside around Apr 19 – May 3, one to three weeks after the median last frost.

How much rain and snow does 62286 get?

About 45.6 inches of precipitation a year and 11 inches of snowfall (NOAA 1991–2020 normals, Sparta 1 W station).

How hot do summers get in Sparta, IL?

The average high peaks at 88 °F in July, with about 35 days a year at 90 °F or more.

What kind of soil does 62286 have?

The USDA soil survey maps Homen at the center of ZIP 62286: silt loam, moderately well drained, pH about 6.5 (neutral).

Did spring come early in Sparta, IL in 2026?

Spring leaf-out near 62286 came on Mar 2 in 2026, 11 days earlier than the 1991–2020 average (Mar 13), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Sparta, IL?

Intermediate onions: the longest day near 62286 is 14 h 49 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 62286 change?

Yes. The 2012 USDA map put 62286 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.