Lawn Dominator

Growing degree days · base 50°F

Growing degree days in Springfield, IL

Season to date · since January 1

4,085GDD

Peak accumulated heat

The season has banked substantial heat. Warm-season grass is at its strongest; cool-season grass may be under heat stress and should not be pushed with nitrogen.

01,0002,0503,0504,100JanFebMarAprMayJunJulAugSepOct
How the heat has built this year. Each day adds the average of that day’s high and low, minus a 50°F base, with nothing added on days that stay below it.Through 2026-10-12 · Open-Meteo archive

This week in Springfield

Springfield, IL added 131 growing degree days this past week, 18.7 a day, reaching 4,085 for the season. Its warmest day added 26.

Daily growing degree day accumulation in Springfield, IL 62701 for the past week, base 50°F
DayAddedSeason total
Tue123,966
Wed213,987
Thu164,003
Fri214,023
Sat204,043
Sun164,059
Mon264,085

PGR reapplication tracking

Plant growth regulator timing uses a Celsius-scale accumulation, not the seasonal Fahrenheit one. This page tracks a 10°C base, which is the Bermuda (warm-season) figure. Trinexapac-ethyl is typically re-sprayed near 200 GDD on cool-season turf and roughly 216 to 230 on warm-season turf, measured from your last application rather than from January. Always follow the product label.

Track GDD from your own spray date →

Soil temperature right now in Springfield, IL

GDD is a trend indicator. Soil temperature is the signal that actually decides pre-emergent and seeding timing, and it is 66.2°F here at 2 inches.

Full soil report for 62701 →

Nearby

Growing degree days near Springfield

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This page recalculates when you load it. The app accumulates GDD for Springfield, IL daily and tells you when your PGR window opens. Free on iPhone and Android.