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

Planting zone for 62673 — Oakford, IL

ZIP code 62673 (Oakford, Menard County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 13 and the first fall frost October 21.

Where ZIP 62673 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 13

First frostOct 21

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 Oakford, 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 Oakford, IL

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 13median — 50% chance of a later frost

Safe for tender plantsApril 28only 10% chance of frost after

First fall frostOctober 21median — 10% chance by Oct 7

Growing season189 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 3 and returns around November 1.

From the NOAA station Petersburg 1e, IL — 9 miles away, elevation 600 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 62673

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 2 – Mar 16

SpinachSow outdoors · Mar 2 – Mar 23

Broccoli, cabbageStart indoors · Feb 2 – Feb 16

Broccoli, cabbageTransplant · Mar 23 – Apr 6

Onion setsPlant outdoors · Mar 16 – Mar 30

PotatoesPlant outdoors · Mar 23 – Apr 6

LettuceSow outdoors · Mar 16 – Mar 30

Carrots, beetsSow outdoors · Mar 23 – Apr 6

TomatoesStart indoors · Feb 16 – Mar 2

TomatoesTransplant · Apr 20 – May 4

Peppers, eggplantStart indoors · Feb 2 – Feb 16

Peppers, eggplantTransplant · Apr 27 – May 11

BeansSow outdoors · Apr 20 – May 4

Sweet cornSow outdoors · Apr 20 – May 4

Cucumbers, squashSow outdoors · Apr 20 – May 4

Fall lettuce, spinachSow outdoors · Aug 26 – Sep 9

GarlicPlant cloves · Oct 7 – Nov 11

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 13) and first fall frost (Oct 21) 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 62673 came on Mar 11 — 15 days earlier than the 1991–2020 average (Mar 26).

average
Mar 262026
Mar 11

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.

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 Oakford, IL.

Soil in Oakford, IL

The soil mapped at the center of ZIP 62673 is Princeton — fine sand, well drained.

TextureFine sanddrains and warms fast; dries out and needs more feeding

pH6.2slightly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter1.25%low — add compost

Hydrologic groupBwater soaks in moderately

Farmland classNot prime farmlandUSDA classification

Map unit: Princeton-Bloomfield fine sands, 15 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 62673; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Oakford, IL

Summer high86 °Faverage high, July

Winter low17 °Faverage low, January

Hot days19days a year at 90 °F or more

Freezing nights121nights a year at 32 °F or less

Growing degree days3,563base 50 °F — the season’s usable heat

Longest day15 h 02 mindaylight on June 21

Shortest day9 h 19 mindaylight on December 21

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

Precipitation37.6 inper year, rain and melted snow

Snowfall15 inper year; 19 days with snow on the ground

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Petersburg 1e, IL (9 mi away); precipitation: Petersburg 1e, IL (9 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

626556a

Kilbourne, IL · 5 mi

626756a

Petersburg, IL · 7 mi

626276a

Chandlerville, IL · 8 mi

626336a

Easton, IL · 10 mi

626596a

Lincoln'S New Salem, IL · 11 mi

Greenview, IL · 13 mi

Illinois planting zones →

Questions about 62673

What planting zone is ZIP code 62673?

ZIP code 62673 (Oakford, 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 Oakford, IL?

The median last spring frost (32 °F) near 62673 is April 13; after April 28 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Petersburg 1e station.

When is the first frost in Oakford, IL?

The median first fall frost near 62673 is October 21, giving a median frost-free growing season of 189 days.

When should I plant tomatoes in 62673?

Start tomato seeds indoors around Feb 16 – Mar 2 and set transplants outside around Apr 20 – May 4, one to three weeks after the median last frost.

How much rain and snow does 62673 get?

About 37.6 inches of precipitation a year and 15 inches of snowfall (NOAA 1991–2020 normals, Petersburg 1e station).

How hot do summers get in Oakford, IL?

The average high peaks at 86 °F in July, with about 19 days a year at 90 °F or more.

What kind of soil does 62673 have?

The USDA soil survey maps Princeton at the center of ZIP 62673: fine sand, well drained, pH about 6.2 (slightly acidic).

Did spring come early in Oakford, IL in 2026?

Spring leaf-out near 62673 came on Mar 11 in 2026, 15 days earlier than the 1991–2020 average (Mar 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Oakford, IL?

Long-day onions: the longest day near 62673 is 15 h 02 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 62673 change?

Yes. The 2012 USDA map put 62673 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.