How To Calculate GDD's

GDD = ((Temperature_max + Temperature_min)/2) - Temperature_base

Max and Min refer to the daily maximum and minimum temperature on a given day.  Base temperature is the minimum temperature at which a plant grows and develops.  Different base temperatures are used for different crops.  For most cool season crops, a base of zero degrees is used, for potatoes, 7 degrees is used and for corn, 10 degrees is used.  GDD's are calculated for each day and added to one another to calculate the amount accumulated up to a certain date.

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