Enhancement of Growth Performances of Ophiopogon japonicas Ornamental Foliage Plant

Ophiopogon japonicus is a perennial, ornamental foliage plant, which belongs to the family Liliaceae. It has a high demand in the local and international export market due to the presence of glossy white-green stripped lanceolate leaves. Improved leaves and plants of O. japonicus will be more popular in the floriculture industry. Hence, objective was to investigate the growth responses of O. japonicus for best potting media and fertilizer treatments. Shoots of O. japonicus trimmed up to 4 cm from the root-shoot junction were potted in two potting media as soil type 1, coir dust, compost and sand as 1:1:1 and soil type 2, sand, coir dust 1:1 by volume. High nitrogen fertilizer, balanced fertilizer and high phosphorous fertilizer were applied as foliar sprays in three concentrations (×1/2, ×1 and ×2 times of the RBG recommended dosages) and distilled water was used as the control. There was a significant (p < 0.05) effect of growing media on the O. japonicus leaf length, plant fresh weight, shoot dry weight, root dry weight, number of leaves and number of shoots. However, there was no significant difference between the control and fertilizer treatments on leaf length, shoot dry weight, number of leaves and number of shoots while there was a significant difference among fertilizer treatments on plant fresh weight and root dry weight. Most effective potting media and fertilizer treatment for O. japonicus were sand:coir dust media (1:1) and Royal Botanic Gardens, Sri Lanka-recommended dosage (RBG) of fertilizer treatments (high nitrogen (2.5 g/L), balanced (1.25 g/L) and high phosphorous fertilizer (2.5 g/L), respectively.