Track the accumulation of heat to predict plant and insect development stages.
Daily Temperatures
°F
°F
Calculation Constraints
°F
°F
Daily GDU Result
Enter temperatures to calculate
About this calculator
Overview
Growing Degree Units (GDU) provide a more accurate prediction of plant flowering or maturity than calendar days because they track cumulative heat accumulation.
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Pro Tips
The 'Corn Method': Uses a base of 50°F and an upper limit of 86°F. Highs above 86 are capped, as growth doesn't increase meaningfully above that point.
Crop Specifics: Check your specific crop variety for its GDU requirements to reach key development stages like silking or physiological maturity.
Pest Management: GDUs are also used to predict the emergence of insect pests, allowing for better timing of scouting and control measures.
Base Temp: The temperature below which plant development essentially stops (e.g., 50°F for corn, 40°F for wheat).
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Fun Facts
"Most corn hybrids require between 2,200 and 2,800 total GDUs to reach harvest maturity."
"Wheat is a 'cool-season' crop and as such generally begins biological growth when temperatures exceed 40°F (4.4°C)."
"Accumulated GDD (Growing Degree Days) is the sum of daily GDUs over the course of a growing season."
Formula: GDU = [(Modified Max + Modified Min) / 2] - Base Temp
