Exoten und Garten Forum
Hardy Palm and Subtropical Board
7,391,085 Messages displayed since 03/03/2007
Message from Brian in Utah
>> -10 and 15 are both a heating degree day I assume?
No. To calculate the heating degree days for a particular day, find the day's average temperature by adding the day's high and low temperatures and dividing by two. If the number is above 65, there are no heating degree days that day. If the number is less than 65, subtract it from 65 to find the number of heating degree days.
Exoten und Garten Forum Hardy Palm and Subtropical Board