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Growing Degree Days

As of 9/4/09 the Growing Degree Day (GDD) accumulation calculated from temperature readings taken at The Westchester County Airport is: 2318.

We will update the above GDD calculation on a regular basis.

What are Growing Degree Days?

Growing degree days (GDDs) as applied to the control of insect/arachnid pests of landscape plants are a measure of accumulated heat calculated by subtracting 50 degrees from the average daily temperature. GDDs may be calculated by plant scientists and other plant specialists using a base other than 50 degrees. In New York State, calculations are made from March to the end of September. Knowing the amount of accumulated GDDs helps plant proffessionals and home gardeners monitor stages of insect/arachnid pest activity or target control to a stage when the pest is most vulnerable.

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