Abstract :
Oncidium orchid is one of the orchids that has high production and attractive appearance, many orchid farmers are developing Oncidium commercially. However, Oncidium orchids have very slow vegetative growth, so there is an effort to increase orchid growth that can be done through fertilization intervals and concentration of Gandasil D fertilizer. This research was carried out from October 2020 to January 2021 at the Handoyo Budi Orchids Garden, Karangploso, Malang. The experimental design used was a factorial completely randomized design (CRD) with 2 factors. The first factor was fertilization intervals every 5 days (I1), once in 10 days (I2), and once in 15 days (I3). The second factor is the concentration of Gandasil D fertilizer which is different with 2 levels: 1 g/L (P1) and 2 g/L (P2). In this experiment, 6 treatment combinations were obtained with 4 replications. Observational data were analyzed using the f test formula (ANOVA) and Duncan Multiple Range Test (DMRT) with an error rate of 5%. The results showed that the interaction of fertilization interval treatment with the concentration of Gandasil D foliar fertilizer gave a significantly different effect on plant height parameters. Key word : Interval, Concentration,Gandasil D, Oncidium orchid