During winter 2021/2022, the first steps were made towards a new growing concept for strawberries. The trial was focused on constant production with fresh June-bearers under variable LED lighting. The trial started at the end of September 2021 and ended in early July 2022.
Lighting is an important factor in spreading the production periods of strawberries under glass. In traditional illuminated strawberry cultivation, cold-stored June-bearers are used, giving multiple crops per year and a peaked production pattern. The concept with the fresh June-bearers is for one crop with almost year-round cultivation, with the aim of achieving a constant production pattern and increasing total production.
The idea behind the project is a fundamental principle that has been tested in research by Plant Lighting. In this new lighting concept, a variable LED spectrum is used during the day, meaning that the plant is illuminated for a long day, and receives energy, but experiences a short day. This is very significant for the control of daylength-controlled crops. June-bearers induce new flowers under short day conditions, so they were chosen in for this concept.
However, the concept is not yet ready for commercial use. In the 2021-2022 season at Delphy ISFC the first steps have been taken towards a concept that can be applied in practice. Conceptual thinking is important in developing a cultivation strategy. Factors like plant structure, outdoor conditions, and plant balance change continuously during cultivation, and they are important, as well as the fundamental principle. This requires a specific way of controlling the climate and lighting. Both the light spectrum and daylight integral are taken into account. In the development of this concept, a strategy has been devised in advance, and both the light spectrum and the daylight integral have been systematically worked out to be able to maintain plant balance.
With low-chill varieties, 15kg of good quality strawberries per sqm were produced in the first year and there is sufficient potential for a constant harvest pattern. The concept is not yet ready for commercial use but offers potential for year-round illuminated cultivation with 17.5 to 20kg of production per sqm and lower electricity inputs per kg of product.
The partners in this project are Signify, NIAB, Fresh Forward Breeding, Flevo Berry and Plant Sciences Europe.