As the farming season begins anew in Europe, it’s important for farmers to stay on top of the growth of their crops. One useful tool to help with this is the concept of Growing Degree Days (GDD). GDD is a measure of the accumulated heat energy that plants need to grow and develop and can be tracked throughout the season to help monitor crop progress.
Large temperature variations across Europe
To illustrate the concept of GDD, let’s take a look at some temperature data from three locations in Europe so far this year: Bodensee in Germany, Kent in England, and Barcelona in Spain. The graph below shows the daily average temperature at each location from January 1st through April 24th of this year.
As expected, Bodensee is much colder than Barcelona. The warm temperatures at the beginning of January pose a risk to plants – it may have been warm enough for some crops to start growing, in which case they are likely to dry out during the rest of winter. GDD calculations indicate that growth started on 7 January in both Kent and Barcelona. In Bodensee, it was 24 March.
From the growth start milestone, GDD accumulates all values above the base temperature throughout the season. The graph below shows the accumulated GDD for each location from January 1 through April 24:
As you can see, even though temperatures were relatively low in January and February, GDD still slowly accumulated in Barcelona and Kent as there were occasional warm days. In Bodensee, nothing happened yet. GDD accumulation increased rapidly in March as temperatures rose, reaching more than 300 GDD in Barcelona.
Better farming decisions with GDD
Tracking GDD can help farmers predict important events in the growing season, such as the emergence of different growth stages and the timing of important pest management practices. By using GDD to monitor plant growth, farmers can also make more informed decisions regarding irrigation, fertilization, and other management practices.
If you are using Farmable to document your activities in the fields, GDD is automatically tracked for you. Based on this, Farmable will be able to give you assistance in assuring your documentation is up to date and compliant with for example requirements of certain pesticides to only be used at certain plant growth stages.
Next season, it will also be possible to predict when milestones will be reached in the fields based on earlier years’ progress and the current year’s weather conditions.
Get off on the right foot by using Farmable this season, and you’ll see new uses of GDD in the near future.