The Interreg PlantGoed project focuses on optimizing the cultivation of strawberry planting material to meet the specific requirements of various cultivation systems. This article discusses three important experiments: the winter cultivation of June-bearers, the illuminated spring cultivation of Sonsation, and the half-yearly cultivations with fresh everbearers. These experiments, carried out by Inagro in consultation with pilot partners PCH and Delphy, investigate innovative cultivation strategies and lighting methods to improve the production and quality of strawberry planting material.
Container-grown June-bearers show a blush in winter cultivation
The first fruits of the winter crop, originating from Sonata and Sonsation planting material produced in the cultivation container, are starting to ripen. For this purpose, dynamically controllable LED lighting was hung in the greenhouse department, which provides 300 µmol/m²/s PAR light. Currently seeing large differences in the amount of fruits between the different cultivation regimes. The control planting material from 2023 has shown the most flowering so far. On the other hand, still see new flower branches emerging in the fresh planting material from the container, which is expected to lead to a more spread-out harvest.
This makes growers all the more curious about the final harvest figures. The cultivation takes place under two lighting strategies with the same energy input: one strategy in which far-red light (1 µmol/m²/s) is administered only at night (from sunset to midnight), and a second strategy in which part of the PAR light is replaced by extra far red (13.5 µmol/m²/s) during the day.
Sonsation darkened in two ways on the tray field
On 9 December, the illuminated spring crop was planted with Sonsation planting material, grown according to different strategies. In order to pack sufficiently heavy planting material on time (15 October), two different darkening strategies were applied on the tray field to ensure early flower initiation. The darkening was carried out by means of a darkening plastic foil. This was placed on the plants daily in the afternoon to reduce the day length in one object to 10 hours and in the other object even to 7 hours. Next to this, there were also plants that were not darkened for control purposes. The darkening was applied from 5 weeks after cutting (6 August) and continued until the change of the flower primordium was observable in the non-darkened plants (5 September). Finally, the plants were planted with 1300 cold hours, and the hope is to be able to harvest the first fruits of the illuminated spring crop by Valentine's Day.
In preparation for half-yearly crops with fresh everbearer
Since November, cultivation has been restarted in the cultivation container. In 2025, two large-scale trials on everbearers will be carried out, testing a wide range of cultivation strategies. Currently, in practice, refrigerated mini-trays are mainly used for everbearers. In the two upcoming cultivations under glass (with plantings early March and May), the aim is to investigate how different cultivation methods can level out the known harvest pattern with peaks and troughs. In these trials, the focus is on fresh plants. For this, various factors have been added to the trial (all together good for 22 test objects):
Source: Inagro