It is almost 2,5 months since a new lighted pepper trial was planted at the Delphy Improvement Centre in Bleiswijk. All the first winter peppers have just been harvested with the first fruits at the end of November. The Improvement Centre has been studying the effects of LED on pepper cultivation together with several partners for five years, intending to achieve a profitable production system for year-round pepper production. In previous years, there was a strong focus on the spectrum; plant balance and optimising the climate conditions. While over 40 kg/m2 productions are no longer a challenge, there is still space for improvement. One of the challenges in the cultivation of peppers is the behavior of the stomata and having the right amount of transpiration. Climate light and light influence transpiration. In this winter trial, we want to investigate which irrigation strategy is most suitable for lit pepper production.
From past trials, we know that far red has an important effect on the stretching and the development of the crop. But far red does not directly contribute to photosynthesis and in the presence of natural sunlight, the amount of far red supplied by the crop can already be sufficient.
For the current trial, the greenhouse at the Improvement Centre is equipped with dynamic lamps. Dynamic lighting solution offers adaptability that can improve the efficiency of lighted pepper cultivation, by adapting the spectrum to the outside conditions. Based on the amount of natural sunlight we will dim far-red and improve the efficiency of the lighting strategy. Currently, we are at a full plant load. The plant load is based on the available light during the winter (LED + sunlight), which is about 16 mol/day. As we have seen a good performance of LED light also depends on the right genetics, different varieties are included in the trial.
Two different EC values are supplied to the crops to investigate the effect of the irrigation strategy. With this strategy, we want to show how EC, transpiration, and nutrient uptake interact in circumstances with 100% LED lighting. This should be proven by influences on leaf quality and production. To understand this process several sensors which measure the conditions in the slab are installed. In the first weeks, we had an equal strategy in the greenhouse and after a few weeks, we started to implement the different EC strategies. Currently, the crop shows a nice balance and the first harvested fruits are showing a good quality, as we are used to in LED pepper cultivation.
To get the best result out of this trial, this is a collaboration between Sollum Technologies; Rijk Zwaan; Enza Zaden; Growficient, and Sendot and Delphy.
Delphy