Blueberry propagation by tissue culture in vitro (micropropagation) has no alternative in mass clonal reproduction of plant material. One of the most important components of a nutrient medium is iron (Fe) which participates in many processes in the plant. At the Faculty of Agrobiotechnical Sciences Osijek (FAZOS, Croatia), a study was conducted to examine the effect of nutrient media modification using chelating iron compounds on growth and development (morphological parameters) of tree blueberry cultivars (Vaccinium corymbossum L.) in vitro. Treatments included the application of two chelated forms of iron (FeNaEDTA and FeEDDHA). After 30 days of cultivation, the analysis of morphological parameters and the evaluation of the multiplication rate performed. Significant differences found between the examined blueberry cultivars in the number of shoots, the number of leaves and multiplication. The best results in morphological parameter (number of shoots, leaf number and multiplication rate) was recorded on cultivar Legacy, then Bluecrop and worst on the cultivar Duke. The difference between the applied treatments (FeNaEDTA and FeEDDHA) was significant only in the number of leaves. No significant difference was found between the applied treatments on the number of shoots, length of shoots and multiplication rate. We assume that the concentration of added chelated form of iron FeEDDHA in the nutrient medium was suboptimal, ie below or above the ideal concentration. Consequently, in the examined cultivars there was only a small (not significant) improvement in multiplication, length and number of shoots. Future research should be focus on determining more optimal concentrations of FeEDDHA iron chelates for each cultivar.