Searching for Suitable Cultivation System of Swiss Chard (Beta vulgaris subsp. cicla (L.) W.D.J.Koch) in the Tropical Lowland

Swiss chard as a leafy vegetable (Beta vulgaris subsp. cicla (L.) W.D.J.Koch) is rarely cultivated in the tropical climate zone because this plant has not been recognized by local farmers. The purpose of this study was to compare the performance of three cultivation systems, i.e., conventional, floating, and bottom-wet culture systems on three Swiss chard cultivars with different petiole colors, i.e., ‘Red Ruby’, ‘Yellow Canary’, and ‘Pink Passion’. The best result was obtained if the Swiss chard was cultivated using the floating system since the water was continuously available by the capillarity force through the bottom hole of the pots, as indicated by the highest number of leaves, total fresh weight, leaf blade dry weight, and petiole dry weight. Fresh weight amongst the three cultivars cultivated in each system did not show a significant difference. ‘Yellow Canary’ produced a larger petiole and heavier fresh weight of individual leaves, but a lesser number of leaves per plant. The leaf area estimation model using the leaf length × width as the predictor, and the zero-intercept linear regression was accurate for all Swiss chard cultivars, as the coefficient of determination was considerably high in ‘Red Ruby’ (0.981), ‘Pink Passion’ (0.976), and ‘Yellow Canary’ (0.982), respectively.