Various fertirrigation techniques for Poinsettia cultivation were put to the test in an experiment conducted jointly by Daniele Guarino, Pietro Marino Gallina and Emanuele Quattrini at the University of Milano and Alberto Pardossi at the University of Pisa. The four techniques used were: drip irrigation to run-off (open); drip irrigation and recycling (closed); sub-irrigation with capillary matting to run-off (open); sub-irrigation using ebb and flow with recycling (closed). From a commercial point of view, plant characteristics obtained with all the irrigation systems were acceptable. Plants using ebb and flow recycling showed greater growth. The principle difference was environmental; the closed systems allowed the utilisation of the same nutrient solution for the entire production cycle thereby saving about 130kg/ha of NPK fertiliser which is the amount lost in drainage in an open run-off system. In both closed systems, the physical-chemical characteristics of the nutrient solution showed a progressive modification but not to the point that made a complete renewal necessary. "Colture Protette" 9 E-mail: paola.testoni@ilsole24ore.com