Overall objective of this Interreg 2 Seas project is to develop a soil-free cultivation system to grow densely sown crops (such as lamb’s lettuce, watercress, spinach or rocket) by upgrading existing early stage prototypes to efficient hydroponic growing systems. This technological innovation (TRL3 to TRL6) will allow soilless cultivation of densely sown crops. Technology transfer will allow for uptake at manufacturers and growers level. Densely sown crops are important for the local economy in the program area. Increasing demand steers production. Development of a novel hydroponic system for densely sown crops in greenhouses, will enable producers throughout the program area to address the challenges they currently face regarding efficient management of crop cultivation and capacity to deal with diseases that reduce yield/quality and revenue. The system will provide for an environmentally and economically viable cultivation, sustainable for producers and more aesthetically and hygienically acceptable to consumers. The project will result in: -base infrastructure to pilot, test and optimize the cultivation of densely sown vegetables using hydroponic-based systems installed in BE, UK and NL; the design for this base infrastructure will be derived from the small-scale prototyping and testing phase -growers guide with cultivation advice for lamb's lettuce, spinach and rocket, addressing key parameters including climate conditions, nutrient solutions and varieties; - technical-economic feasibility study with final design specifications, automation concepts and a profitability report; The wide horticultural chain can benefit from these outputs. In particular, they will offer growers new opportunities to meet increasingly strict demands from legislation and retail without compromising crop yield and quality. Manufacturers will also benefit from the project outputs through supply and installation of (parts of) the system. As a result, competitiveness of businesses in the program area will increase.