Promoting Vanda tricolor growth at the acclimatization stage: influence of rice washing water and wood charcoal-fern root medium

Abstract Vanda tricolor is a type of orchid found exclusively on Mount Merapi’s slopes. Various efforts have been undertaken to conserve this orchid, including the growth of this species by in vitro culture and acclimatization. However, the success of orchid growth during acclimatization is heavily influenced by the planting medium and nutrients. This study aims to identify the optimal medium and nutritional source for the acclimatization of Vanda tricolor . This research was carried out in Completely Randomized Block Design using two factors. The first factor is the medium composition divided into three treatments, namely, wood charcoal, fern roots and mixed of wood charcoal and fern roots. The second factor is the source of nutrients divided into three treatments, namely no nutrients added, monosodium glutamate and rice washing water. Each treatment was replicated three times, with each replication comprising three samples. The data obtained from quantitative observations were evaluated using Analysis of Variance with a significance level of 5%. The analysis results indicated no reciprocal effect between the medium type and nutrient source on the growth of Vanda tricolor during the acclimatization phase. The findings demonstrated that the utilization of a wood charcoal-fern root medium had a more favorable impact on the acclimatization process of the Vanda tricolor orchid, as evidenced by increases in plant height, leaf number, leaf length, and leaf width. On the other hand, rice washing water is a more appropriate nutrient source for the growth of Vanda tricolor .