Abstract
Conventional and integrated fruit growers have the possibility to use Carbaryl and Benzyladenin 2 thinning agents, which allow crop regulation at a relatively late stage (10 – 16 mm of fruit size). At that stage, organic fruit growers can only thin by hand, which is quite time-consuming. A few surveys show that reducing net photosynthesis after blossom increases the June drop. This could be an interesting new approach for organic apple orchards. In 2003 a trial was carried out at the Laimburg Research Station to understand if application of high amounts of bentonite could achieve that goal. The results were encouraging, but still not recommendable to practical growers.