The Effect of Different Concentrations of Nitrogen and Potting Media Composition on Some Growth Characteristics of Poinsettia (Euphorbia pulcherrima) cv. Noel Red

To investigating the effects of various concentrations of nitrogen (180, 230, 280 and 330 mg L-1) and potting media composition (peat moss:perlite or cocopeat:perlite as 2:1 V/V) on some growth traits of Euphorbia pulcherrima,  a factorial experiment was conducted based on a completely randomized design with 8 treatments and 3 replications. The results showed that the highest height, plant canopy diameter and protein content eamed by using of were observed in plants grown at the concentration of 230 mg L-1 N in cocopeat and perlite media. The concentration of 230 mg L-1 N increased the bract and leaf area in comparison with the other treatments. The concentration of 280 mg L-1 of nitrogen with cocopeat and perlite media caused the maximum amount of the Mg content in plant leaves tissue. Using of peat mass and perlite and 330 mg L-1 of nitrogen resulted in the highest bract anthocyanin and potassium content. Generally, the results of the study showed that the concentrations of 230 and 280 mg L-1 nitrogen and the combination of cocopeat and perlite as a media improved the growth indices and qualitative characteristics of Poinsettia.