Is it possible to manage irrigation in pepper cultivation based on data? That was the question that prompted sensor manufacturer Wireless Value to begin developing a solution. In substrate producer Van der Knaap Group, the company found a partner to develop and test a weighing system, in a collaboration that proved successful.
The next step was scaling up. Wireless Value worked together with BBM Company to expand the system for practical use. During the past winter period, several systems were installed at pepper and eggplant growers, who are now gaining experience with technology that generates absolute irrigation values.
© Wireless Value
Because the weighing system must not deviate from the other gutters in cultivation for optimal measurement results, it was ensured in the design that the substrate mat is well-ventilated within the weighing system.
Origin of the system
It was a tomato grower who was already using Wireless Value load cells for cultivation on coco substrate that introduced the sensor company to Van der Knaap Group. Together, they developed a complete weighing setup tailored to pepper cultivation. The new setup filters out the effects of crop movement and harvesting from raw irrigation data, producing cleaner figures that give growers better insight for making irrigation decisions.
A prototype is installed at Van der Knaap's innovation centre, 'de Kas', in Honselersdijk. The substrate producer's technical team developed a construction in which the weighing unit is suspended via load cells from a frame that is independent of the greenhouse structure. Van der Knaap is now taking the work a step further.
"They are going to use the setup to determine watering strategies tailored to specific substrate types," says Kees van Vliet, Agri account manager at Wireless Value.
© Wireless ValueWeighing system in eggplant cultivation
Scaling up with a scalable system
When word spread in the market about what Wireless Value was developing, interest from pepper growers grew quickly. In response to crop failure issues, a significant number of growers had already switched to organic substrates, and this renewed the demand for accurate irrigation monitoring in pepper cultivation.
To introduce growers to the concept, Kees van Vliet invited groups of growers to visit the Honselersdijk installation on several occasions. Around the same time, Wireless Value made contact with BBM Company.
"Our initial idea was that growers could build their own supporting structure, similar to what Van der Knaap had done, and integrate the weighing unit into their greenhouse," says Van Vliet. It quickly became clear that growers were not always willing to do this. It also became apparent that without a standardised construction, achieving reliable weight measurements would be difficult. Accurate weighing demands a robust setup, and that is best controlled in-house.
Together with BBM Company, Wireless Value mapped out the range of greenhouse types in which the equipment would need to be installed. "It turned out there is enormous variation in V-systems and four-row systems," says Van Vliet. "I think I visited 25 to 30 greenhouses, each slightly different: single gutters, double gutters, or different truss configurations."
BBM Company co-founder Boris Prins used this information to design a construction that is robust, strong, and suitable for a wide range of greenhouse configurations without requiring major modifications at each installation. "The unit we developed is longer than the Van der Knaap version," says Prins. "The first one is 4.70 metres long. To make transport manageable, it comes in two sections that are easy to connect on site." His business partner Brent van Paassen adds: "What is in place now is straightforward to use. We wanted to create something that would work across as many different growing configurations as possible."
© Wireless ValueExample of irrigation data from a Canadian grower
Application in cultivation
It quickly became apparent that not only pepper growers were interested, aubergine growers also wanted to work with the setup. Units have since been installed in greenhouses growing both crops.
"With this new design, it is possible to install units between roughly late October and early February. We even hung one in early February," says Van Vliet. "In that case, the gutter had already been installed and the plants had grown significantly, but the design of the construction meant we could still mount the unit mid-season. That gives us a lot of flexibility."
Once operational, the setup helps growers establish a well-calibrated irrigation line. "A grower now sees two lines: an evaporation line and a line showing what is happening inside the substrate," explains Van Vliet. "One of the advantages is that we work with absolute values. 100 grams of weight equals 100 millilitres of moisture. That makes it more actionable than expressing weight loss as a percentage."
To arrive at clean data, Wireless Value filters out the effect of harvesting from the weight measurements. Work is also underway with Van der Knaap to use the equipment to track the daily increase in fresh weight. Some growers are already looking at further applications. "One grower who has been working with our setup in practice added a PAR sensor to it," says Van Vliet. "That way, he can measure grams per mole."
Development has accelerated considerably. "We moved faster than we originally expected," Van Vliet acknowledges. "And we are far from finished. It is very helpful that so many growers are willing to think along with us, also with an eye to future functionality." Van Vliet's own background in the substrate business has proven useful throughout the process. "I enjoy working on optimising irrigation. This project has completely reignited that passion."
© Wireless ValueThe weighing system's data goes via the internet to Wireless Value's portal. Here, the weighing data is processed, so that data can later be shared via an API. Additionally, it is now also possible to send bundled raw weighing data directly to the grower's climate computer. "In this way, you can not only monitor, but a grower can also start steering directly based on weighing data using the data."
For more information:
Kees van Vliet
Wireless Value
Mob.: +31 6 411 537 27
Tel.: +31 591 633200
[email protected]
www.wirelessvalue.nl
BBM Company
De Derde Hoeve 9
2676 CR Maasdijk
+31 6 34 93 08 19
[email protected]
www.bbmcompany.nl
