What are Growing Degree Days (GDD)?

GDD, also known as heat units, are a measure of heat accumulation used to predict plant and pest development rates. Development is limited when the temperature is below a minimum base temperature.

What is the 'Base Temperature'?

The base temperature is the lowest temperature at which a specific plant or pest will grow. Below this temperature, development stops. Common base temperatures are 50°F (10°C) for corn and 40°F (4.4°C) for wheat.

How do I use the daily GDD value?

You should calculate the GDD for each day and add them together over the growing season. The total accumulated GDD can then be compared to published values for predicting growth stages (e.g., flowering) or pest emergence.

Growing Degree Days (GDD) Calculator

Track heat accumulation to predict plant and pest development.

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