Growing degree-days

From Glossary of Meteorology
Redirect page

Redirect to:

growing degree-day

(Abbreviated GDD.) A heat index that relates the development of plants, insects, and disease organisms to environmental air temperature.

GDD is calculated by subtracting a base temperature from the daily mean temperature and GDD values less than zero are set to zero. The summation over time is related to development of plants, insects, and disease organisms. The reference temperature (base temperature) below which development either slows or stops is species dependent. For example, cool season plants (canning pea, spring wheat, etc.): base temperature is 40°F (5°C); warm season plants (sweet corn, green bean, etc.): base temperature is 50°F (10°C); and very warm season plants (cotton, okra, etc.): base temperature is 60°F (15°C).
See degree day, heat unit

Copyright 2022 American Meteorological Society (AMS). For permission to reuse any portion of this work, please contact [email protected]. Any use of material in this work that is determined to be “fair use” under Section 107 of the U.S. Copyright Act (17 U.S. Code § 107) or that satisfies the conditions specified in Section 108 of the U.S.Copyright Act (17 USC § 108) does not require AMS’s permission. Republication, systematic reproduction, posting in electronic form, such as on a website or in a searchable database, or other uses of this material, except as exempted by the above statement, require written permission or a license from AMS. Additional details are provided in the AMS Copyright Policy statement.