As part of the trial, the Axia Macxize XR variety was transplanted 24th of September in week 39, where light levels are increased to 350 µmol/m2/s, compared to 300 µmol/m2/s in the last season.
The trial is in partnership with Ridder for its climate computer and screens, Wireless Value for sensoring, and Normec Groen Agro Control for advice on nutrient and water strategy. Seed supplier Axia will be a new addition to the existing group of research partners.
Exploring further energy efficiencies
The trial will test two different growing scenarios—multi-channel LED toplighting compared to a combination of LED toplighting and interlighting, keeping the total daily light integral (DLI) the same while optimising spectrum and light intensity. For this, Signify will install its four-channel Philips GreenPower toplighting force in the entire greenhouse and Philips GreenPower LED interlighting in one half of the greenhouse to provide extra light directly within the canopy.
“We expect the combination of toplighting and interlighting to result in a better light use efficiency (LUE) by improving the distribution of both light and temperature in the crop,” comments Marcel Raats, plant specialist for Philips Horticulture LED Solutions at Signify. "Our goals this year are to gain a better understanding of the radiation balance at the top of the plants, and to finetune screen steering to further optimise the energy input together with Ridder."
Continued focus on precision irrigation
“As in the previous two years, we will use Grodan’s stone wool growing media to precisely manage the water and nutrient uptake, enabling us to create a strong, generative plant balance aligned with the low heat input. In collaboration with Normec Groen Agro Control, we will also explore the possibility of improving the nutrient uptake to avoid green spots and blotchy ripening in an adjusted drip composition compared to the standard used in practice. This will facilitate sufficient nutrient uptake and good fruit quality, while maintaining production,” states Andrew Lee, Knowledge Manager at Grodan.
Both the vertical plant temperature and the fruit temperature will be closely monitored. The data will inform a better crop balance and steerability in the development speed – all the way from the young fruits in the head of the plant to the maturing fruits in the lower part of the canopy.
Building on proven results
The research partners have already proven that low-energy tomato cultivation can be accomplished, with last year's results yielding 18.24 kg/m² with a Brix level of 9.32 and an average fruit weight of 12.20 g.
The partnership continues to refine its approach with a combination of active dehumidification, screens with higher insulation value, closing the screens for more hours in the day, and minimising the rail pipe operation. By dynamically adjusting LED light spectra i.e., switching off less efficient colors when conditions allowed, electricity costs were reduced by a further 2% this year.
From an irrigation perspective, controlling the leaf area index (LAI) with low-nitrate feed strategies optimised the canopy development, while fine-tuning the K, Mg, and Ca ratios led to enhanced nutrient uptake and fruit quality. The dedicated dehumidification system was key in maintaining ultra-stable greenhouse climate conditions to support consistent crop growth, setting the tone for the future cultivation of high-quality tomatoes, using less energy.
About Grodan
Grodan is the global leader in supplying innovative, sustainable stone wool growing media solutions for the professional horticulture industry, based on Precision Growing principles. These solutions are applied to the cultivation of vegetables and flowers, such as tomatoes, cucumbers, sweet peppers, egg plants, roses and gerberas. Sustainability plays a prominent role within Grodan, from the manufacture of stone wool substrates to recycling solutions. Grodan was founded in 1969 and is active in more than seventy countries worldwide. The head office is located in Roermond, the Netherlands. For more information, please visit www.grodan.com.
About Signify
Signify (Euronext: LIGHT) is the world leader in lighting for professionals and consumers and lighting for the Internet of Things. Our Philips products, Interact connected lighting systems and data-enabled services, deliver business value and transform life in homes, buildings and public spaces. In 2022, we had sales of EUR 7.5 billion, approximately 35,000 employees and a presence in over 70 countries. We unlock the extraordinary potential of light for brighter lives and a better world. We achieved carbon neutrality in our operations in 2020, have been in the Dow Jones Sustainability World Index since our IPO for six consecutive years and were named Industry Leader in 2017, 2018 and 2019. News from Signify is located at the Newsroom, Twitter, LinkedIn and Instagram. Information for investors can be found on the Investor Relations page.
For more information, press only:
Grodan
Lieke van Stekelenburg
E-mail: lieke.van.stekelenburg@grodan.com
&
Emmanouela Alexopoulou
E-mail: emmanouela.alexopoulou@grodan.com
Philips horticulture LED solutions by Signify
Daniela Damoiseaux – Global Marcom Manager
Tel: +316 40578311
E-mail: Daniela.damoiseaux@signify.com
