When it freezes in spring, sprinkling water over fruit trees is a commonly used method for protecting the fragile flower buds in most of the Netherlands. In some case, this method is successful. Unfortunately, it is costly and has an impact on farmers families, which have to stay awake all night. Besides, this method is limited by the ground water level and quality (not to salt) and cannot be applied everywhere. Other strategies to prevent fruit frost make use of e.g. fire candles throughout the field or use heat canons to locally enhance the temperatures. However, little is known about the effectiveness of each of these methods. By linking numeric modelling with field experiments the researcher aims to assess the effectiveness of the various known frost preventing measures.

Field experiments with huge ventilators (10m height) in an orchard have shown that they are very efficient in mixing colder and warmer air layers. Through a spider web of glass fibers in the field they could map the temperature response due to ventilator operation. The numerical models allowed the researcher to determine which interventions – rotation speed or location - increased the effectiveness of the ventilator. Subsequently, the researchers are also developing an app which could map the temperature field, real time, based on tiny autonomous sensors that are located in the field. Such an app is suggested to support farmers in making decisions on when and where to initiate frost prevention measures.