Abstract: The experiment concerned the 3 years．old plants of pot azalea (Rhododendron simsii ‘Mission Bell’)were designed as 30 replicates to conduct studies on media formula with hydroponics．In terms of plant height and width，leaf length and width，fresh and dry mass，root development and leaf chlorophyll content(SCDSV)，the results indicated that M 1(Peat moss 3+Vermiculite 3+Perlite 3 by volume)formula was the best media for soilless culture of pot azalea plants．the medium formula containing coconut was
not suitable for soilless azalea culture． By analyzing physical and chemical properties of different media formu1a before and after subirrigation with Sonneveld nutrient solution．it was found that pH values tended to 5 and
EC values increased a lots as a result of salt accumulation in media at a closed system of hydroponics：all the contents of total N， available P，K，Ca， Mg，and CEC in 5 media form ula increased as wel1． Finally，contents of macronutrients and concentrations of micronutrient in plants of ‘Mission Bell’were almost around the optimal levels of plant growth．

Key words: Ebb and flow subirrigation bench system, Azalea, Media formula, Nutrient element