From the lab to the greenhouse: PEATLESS monitoring systems are now running
CESENS has installed monitoring equipment at PEATLESS trial sites in Spain and Italy, adapting the technology to ornamental plants, mushroom cultivation and vegetable seedling production.
In a previous PEATLESS article, CESENS described the calibration of sensors for alternative growing media and the initial development of a continuous weighing system for seedling production.
Those monitoring solutions have now moved beyond the workshop. Since spring, equipment has been installed and collecting data at trial sites in Spain and Italy, covering the three horticultural systems addressed by PEATLESS: ornamental plants, mushrooms and vegetable seedlings.
The installations have confirmed that a single monitoring solution cannot be applied in exactly the same way to every crop. Each production system has required a specific configuration adapted to its containers, facilities and growing conditions.
Monitoring ornamental plants in Italian nurseries
For ornamental plant production, dielectric sensors have been installed directly into the side walls of the containers. They measure water content, temperature and salinity every 15 minutes, providing continuous information about conditions inside the growing media.
A total of 36 measurement points are currently operating across three nurseries in Italy. The system is being used to compare five alternative growing media formulations with a conventional peat-based control.
This setup makes it possible to follow changes in each formulation throughout the trial, rather than relying exclusively on measurements taken at specific moments.
Adapting the equipment to mushroom growing rooms
The same type of dielectric sensor is being used in mushroom cultivation, but the characteristics of the growing rooms required several technical adaptations.
Unlike outdoor nurseries, mushroom growing rooms have no daylight. The monitoring stations therefore cannot depend on solar energy and must operate using mains power.
The construction of the rooms created an additional challenge: their panels completely block the radio signals used to transmit the measurements. To maintain communication with the monitoring platform, the antennas had to be moved outside the growing rooms.
The monitoring principle may be similar, but its implementation must respond to the conditions of each horticultural system.
A different solution for plug trays
Vegetable seedling plug trays presented the most difficult monitoring case.
Conventional moisture sensors cannot provide representative readings inside individual tray cells. The volume measured by any sensor currently available on the market is considerably larger than a single cell.
CESENS therefore adopted a different approach: weighing the complete tray instead of measuring moisture within an individual cell.
A total of 12 precision scales are now operating at CITA’s facilities in Zaragoza. These scales track the water balance of complete trays with a precision of a few grams.
Monitoring the entire tray provides a more integrated view of water behaviour and allows the different growing media to be compared without depending on readings from one small section of the tray.
Monitoring designed around real production conditions
The installations in Spain and Italy represent an important step in the development of the PEATLESS monitoring systems. They also demonstrate why digital tools must be adapted to the physical characteristics of each crop and production environment.
For ornamental plants, sensors can be inserted into individual containers. In mushroom growing rooms, power supply and signal transmission become essential considerations. For plug trays, weighing the complete production unit offers a more representative solution than conventional moisture sensors.
These installations form part of the PEATLESS process to test and validate alternative growing media under different horticultural conditions. The data collected will support the next stage of the work: understanding how the materials behave and translating continuous measurements into practical information for growers.
