On tests currently being conducted at Wageningen UR Greenhouse Horticulture and GreenQ Improvement Centre, Willem Valstar of GreenQ says that the crops are doing reasonably well for the time of year and the plant age looks good. Botrytis is under control.
Valstar: "Against conventional wisdom we kept the lights on in the dark period of week 20 - 22. In week 18 we stopped lighting, starting with only LED lights in week 20, then we also switched on the SON-T lamps. It was clear that hybrid lighting is an advantage in this situation. The plant load under diffuse glass is somewhat higher than under clear glass. In the GreenQ Improvement Centre, where the glass is diffuse, the crop was very poor. The extra light in May did the trick. I think crops under diffuse glass are better able to recover."
"All in all energy efficient cultivation is going quite well. With 20 cubic meters of gas, we’re now slightly above the forecast of 19.5 cubic meters of gas, but that is justifiable considering the cold Spring.”
Source: www.tuinbouw.nl