Growing Degree Days: What is it and why it matters in sustainable farming

Growing Degree Day (GDD) is a good indicator of crop development, as well as the occurrence of diseases and pests.

GDD is defined as the accumulation of average daily temperature, but only between the “base temperature” (the lower threshold of vegetation) and the highest, so within the temperature limits in which plant growth and development are possible.

In the absence of extreme conditions, droughts, excess moisture or diseases, plants (and insects) develop and grow in accordance with the air temperature, that is, the energy required for the growth and development of plants. Thus, the total accumulated sum of active temperature (GDD) can be used to analyze crop progress and predict the occurrence of diseases and pests, then to compare different growing seasons, while the long-term average of GDD is useful for evaluating crop phenophases and harvest time. We will also use it to plan drone shots in specific phenophases.

Stay informed with our latest sustainable farming insights and exclusive content. Subscribe now.

Δ

By submitting your email, you consent to subscribe to our e-newsletter to receive the latest LoginEKO updates. You can withdraw your consent at any time, more info here.

For example, for corn, GDD stands from 10 to 30 degrees Celsius, and for sunflower from 8 degrees Celsius onwards, while for wheat it starts from 4 degrees Celsius. We can see that GDD differs among varieties, so we determine the values for our specific crops by following the phenophases in our fields.By collecting data through time, we will be able to adapt it and improve accuracy of our GDD solution.

There are various tools on the internet to calculate GDD, but most of the time we don’t know what data they use or what formula they use. And so, agronomists at LoginEKO, together with our engineers, developed our own method. It increases accuracy by using higher logging frequency and spatial weather data for all of LoginEKO fields.

Our GDD calculation method covers the following:

• calculating GDD based on data from our meteobot weather stations using five popular calculation methods;
• enabling easy selection of the base temperatures;
• facilitating the comparison of GDD in different fields with the same crop.

This helps us collect data on phenophases in our fields, calculate evapotranspiration, and make informed decisions when we are planning scoutings, disease prediction, weed control and other operations.

GDD Calculator will be integrated into our Farming Software to help farmers plan their field operations like weed control, harvest, and notify them about times to check for pests and diseases.