In response to challenges posed by unsustainable fertilizer practices, this study aimed to investigate the effects of fertilizer rate and split application on cauliflower growth and yield under protected house conditions. The cauliflower variety “White Flash” (Brassica oleracea var. botrytis) was grown in open-top grow bags with coconut coir potting media. Albert's solution (N: 10.6%, P: 9.3%, K: 16.3%, Ca: 11%, Mg: 2.25%) was used as fertilizer. Three fertilization rates (R1: 1.0, R2: 1.5, R3: 2.0 g/plant/day) and three split applications (S1: 1, S2: 2, S3: 3 splits/plant/day) were randomly allocated in a two-factor factorial completely randomized design, each with four replicates. The control group followed current farmer practices (R3S1) with daily treatment applications. The average temperature and relative humidity inside the protected house were 29℃ and 84%, respectively. Growth variables, including plant height and leaf number, were measured biweekly, and leaf area was measured at harvesting. Fresh plant weight, curd weight, and curd diameter were recorded at harvest to assess yield. The interaction between rate and split application significantly (p<0.05) affected cauliflower growth and yield. Among the treatments, significantly, the highest curd weight (490.95 g), curd diameter (13.8 cm), and harvest index (40.9%) were observed in the R2S3 treatment. This study concludes that a 1.5 g/plant/day fertilization rate with 3 split applications of Albert's solution is cost-effective and enhances cauliflower growth and yield under protected house conditions in Sri Lanka's Low Country Wet Zone.
Karunarathne et al. (Thu,) studied this question.