Abstrak
Bougainvillea (Bougainville mirabilis) is an ornamental plant that is very popular among the public. In general, its propagation is done vegetatively, namely by stem cuttings method. This method depends on the ability of the stem in growing the root. The indicators of problems in the stem cuttings are the quality of seeds and improper fertilization, which have a negative effect on the roots and shoots growth. This study was to determine the interaction between the application of NPK fertilizer and the length of bougainvillea cuttings on its growth and flower blooming. This study employed a factorial experiment in a Randomized Block Design (RAK) with several combinations of treatments. There were 12 treatments, each of which was repeated 3 times. The first factor is NPK mutiara (P) consisting of 4 levels, namely P0 = control, P1 = 2 grams, P2 = 4 grams, P3 = 6 grams and the second factor is cutting lengths (F) consisting of 3 levels, namely F1 = 15 cm, F2 = 20 cm, F3 = 25 cm. The results showed that the application of NPK fertilizer and different cutting lengths showed no signification effect on the vegetative and generative parameters, .i.e., the number of leaves, number of shoots, shoot length and number of flowers. However, it was found that there was an interaction between the NPK fertilizer and the length of the cuttings. The P1F3 treatment (NPK fertilizer 2 g + cuttings length 25 cm) showed the most leaves at 4-14 WAP, the P3F3 treatment (NPK fertilizer 6 g + cutting length 25 cm) gave the best results on other indicators of shoots at 8 WAP, the shoot length at 6-14 MST, and also the number of flowers at 10-14 MST