The Testing Station for Olericulture (PSKW) supports the vegetable production sector in its efforts to bring about developments leading to an innovative, competitive and sustainable position in horticulture. The trial was conducted in two identical adjacent greenhouses covering an area of over 200 m2. When lit, these greenhouses were separated from one another by a light-tight screen.
The red lettuce varieties showed better red coloration in the LED greenhouse in the winter (December-March) than the ones in the reference greenhouse. The red coloration was evaluated up until March on the basis of a color chart. No difference was observed between the red coloration of the lettuce with the high blue LED treatment and the ‘normal’ LED treatment.
In addition, in four of the six harvests in which there was damage from edge burn, less edge burn was observed in the LED greenhouse. Besides improved red coloration, the Red Oakleaf lettuce was also more compact, with the same head weight, and the Lollo Rossa in the LED greenhouse was heavier by a significant amount of 20 grams”, says Isabel Vandevelde, supervisor of the trial.