An optimized growth climate is essential to optimize crop growth. According to the principles of Plant Empowerment, crop growth is determined by the three plant balances. Therefor the greenhouse climate needs to support the crop to keep it’s balances in balance at all times. Team AuTomatoes used the principles of Plant Empowerment in their growth strategy during the Autonomous Greenhouse Challenge. They won the Challenge because they focused on the plant and it’s balances when developing their algorithms and solutions for growers.
So how did they do this? This article explains all about the assimilates balance and how team AuTomatoes kept it in balance at all times.

The assimilates balance is the balance between the production and consumption of assimilates. To optimize growth it is essential that the production of assimilates is as high as possible and that the use of assimilates is stimulated to a maximum. To keep production and usage of assimilates in balance there must be a good ratio between PAR light sum (production of assimilates) and the average temperature (usage of assimilates) at all times.

To optimize the production of assimilates team AuTomatoes developed a new sensor, called the Light Penetration Ladder. This sensor measures the amount of light in the greenhouse at three levels: at the top, middle, and bottom of the crop. These measurements provide insights in the actual amount of light that is penetrating the canopy, and is received by the leaves on different levels in the crop. The team used this as the base for their leaf pruning strategy. This way they could control the light use efficiency to optimize the production of assimilates.

In order to optimize the usage of assimilates the team developed two control algorithms. The Ventilation Optimization Control algorithm controls the vent positions according to the desired setpoints for temperature and humidity. In addition, the Temperature Optimization Control algorithm realizes the right balance between the light sum and average 24-hour temperature. Together these algorithms allowed the team to optimize the average temperature in their greenhouse, and therefore the crop’s usage of assimilates.