Nerium oleander plants are important ornamental trees, much cultivated in urban centers. This species is propagated by cuttings, but rooting percentage is very low and there are no studies on the factors that influence this process. Therefore, the objective of this work was to study the effect of the harvesting time and the indolebutyric acid (IBA) on the rooting of cuttings of two Nerium oleander varieties, determined by flower color (pink and white). The experiments were conducted at UNESP, Campus of Jaboticabal, São Paulo State, Brazil, during summer and winter. The experimental design was in randomized blocks and the treatments were organized in a 2 x 2 x 4 factorial arrangement (two varieties, two harvesting times and four IBA concentrations - 0, 1000, 2000 and 4000 mg kg-1). The evaluations were done 60 days after the cuttings, and the following variables were observed: percentage of rooting, mean root number, mean root length and mean root dry mass. Rooting of the two varieties was higher in summer (97%) when compared to winter (77% and 56% respectively for the pink variety showed higher rooting percentage and root dry mass in winter and higher number and length of roots in summer; the indolebutyric acid concentrations of 1000 and 2000 mg kg-1 increased the rooting percentage, and the 2000 mg kg-1 one increased root number, root length and root dry mass.
Cuttings; IBA and Asexual propagation
