Planting zone for 61428 — Dahinda, IL
ZIP code 61428 (Dahinda, Knox County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is April 21 and the first fall frost October 20.
Where ZIP 61428 is
Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoomNot 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.
Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 5b means →
Frost forecast — next 7 nights
live from the National Weather ServiceLoading the forecast for Dahinda, 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 Dahinda, IL
A hard freeze (28 °F) usually ends around April 9 and returns around October 29.
From the NOAA station Knoxville, IL — 9 miles away, elevation 728 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 61428
Counted from the median last spring frost (Apr 21) and first fall frost (Oct 20) 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 61428 came on Mar 11 — 22 days earlier than the 1991–2020 average (Apr 2).
Apr 22026
Mar 11
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 5b in Illinois
584 plants native to the lower 48 states, recorded in Illinois, and rated by the USDA to survive −15 °F or colder — the bottom of zone 5b. Each links to its USDA PLANTS profile.
Trees 77
Shrubs 102
Wildflowers & perennials 210
Grasses 173
Vines 7
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 Dahinda, IL.
Soil in Dahinda, IL
The soil mapped at the center of ZIP 61428 is Hickory — silt loam, well drained.
Map unit: Hickory silt loam, cool mesic, 35 to 60 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 61428; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.
Climate in Dahinda, IL
Average high and low, by month
Precipitation by month inches · ❄ = snowfall
NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Knoxville, IL (9 mi away); precipitation: Knoxville, IL (9 mi away). Daylight is calculated from latitude.
Nearby ZIP codes
All 8 nearest ZIP codes share zone 5b.
Questions about 61428
What planting zone is ZIP code 61428?
ZIP code 61428 (Dahinda, IL) is in USDA hardiness zone 5b on the 2023 map: the coldest night of an average winter reaches −15 to −10 °F (−26.1 to −23.3 °C).
When is the last frost in Dahinda, IL?
The median last spring frost (32 °F) near 61428 is April 21; after May 6 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Knoxville station.
When is the first frost in Dahinda, IL?
The median first fall frost near 61428 is October 20, giving a median frost-free growing season of 181 days.
When should I plant tomatoes in 61428?
Start tomato seeds indoors around Feb 24 – Mar 10 and set transplants outside around Apr 28 – May 12, one to three weeks after the median last frost.
How much rain and snow does 61428 get?
About 40.5 inches of precipitation a year and 25 inches of snowfall (NOAA 1991–2020 normals, Knoxville station).
How hot do summers get in Dahinda, IL?
The average high peaks at 84 °F in July, with about 13 days a year at 90 °F or more.
What kind of soil does 61428 have?
The USDA soil survey maps Hickory at the center of ZIP 61428: silt loam, well drained, pH about 6.8 (neutral).
Did spring come early in Dahinda, IL in 2026?
Spring leaf-out near 61428 came on Mar 11 in 2026, 22 days earlier than the 1991–2020 average (Apr 2), according to the USA National Phenology Network Spring Index.
What kind of onions grow in Dahinda, IL?
Long-day onions: the longest day near 61428 is 15 h 07 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).