Effects of Rate and Frequency of Foliar Fertilizer Application on Growth and Development of <I>Vanda</I> Orchid ‘Pat Delight’

Abstract

For Vanda production, fertilizer application was one of the factors which affected plant quality. This research was aimed to study the effects of fertilizer application methods on growth and development of Vanda. Five year olds of Vanda ‘Pat Delight’ plants were selected for experiment. Plants were supplied with 21-21-21 fertilizer solution by 2 factors i.e. Factor 1: fertilizer concentration rates i.e. 1) at 20 g/20 L 2) at 40 g/20 L and 3) at 60 g/20 L; Factor 2: two frequency of applications i.e. 1) once a week and 2) twice a week were supplied to plant with 100 mL/plant. The experimental design was factorial in completely randomized design with 3x2 treatments plus 1 treatments as control with 10 replications. Growth and development were recorded within 12 months i.e. stem height (measured from base of stem to terminal point), leaf greenness (SPAD unit), number of flowers/plant, flower diameter, inflorescence length, and nitrogen (N), phosphorus (P) and potassium (K) contents in leave, root and stem samples. The results found that using 40 g/20 L once a week (treatment 2) could promote the best growth and development and flower quality but not significant difference from managing with maximum fertilizer application treatment (treatment 6: 60 g/20 L twice a week). However plant nutrient contents in roots and stems were lower than treatment 6: 60 g/20 L twice a week. However, plant nutrient contents in leaves were not significant difference from treatment 6: 60 g/20 L twice a week.