Poland has one of the smallest fresh water resources in Europe. Due to variability of Polish climate, irrigation became an indispensable element of intensive horticultural production. Recent study has shown that Polish farmers do not use any criteria to estimate plant water requirements for controlling irrigation, which leads to waste of water and energy. This is because userfriendly technologies enabling rational use of water resources are not easily available. The objective of the project is to develop an effective system for control of irrigation in ornamental nurseries, based on measurements of plant parameters, soil conditions and climatic data. To realize this approache the crop coefficient (k) for several important nursery species should be determined. Also the method of restricted irrigation (Regulated Deficit Irrigation - RDI) to control plant shape and plant quality will be tested on several important nursery cultivars. Additionally quantitative and qualitative evaluation of drainage water originated from container ornamental nurseries will be performed. The technology developed within the project will become the key element of the strategy of rational plant irrigation in ornamental nurseries. This is novel, hitherto not implemented approach to the problem of rational irrigation water use in plant production ...