Closed-loop re-circulation was installed in a 5 m long row section in each of the two greenhouse compartments. A 200 l drain collector below the soil surface adjacent to the 5 m section collected drainage that was re-pumped into the irrigation storage tank located outside the greenhouse. Fresh
solution was added daily to replace plant water uptake. The threshold value of EC for dumping and replacing the irrigation solution was 4.0 dS m1. Nutritional level and pH of the solution were controlled in the irrigation container