Influence of Plant Spacing and NPK Fertilizers on Growth and Yield of Broccoli

An experiment was conducted at the Horticulture Farm, Bangladesh Agricultural University, Mymensingh. The study aimed to investigate how plant spacing and NPK fertilizers influence the growth and yield of broccoli. The experiment used a randomized complete block design with three replications. The treatments included three plant spacings: S1 (60 cm × 50 cm), S₂ (60 cm × 40 cm), and S3 (50 cm × 50 cm), and four doses of NPK fertilizer: F0 (N0P0K0 kg/ha), F1 (N₁₀₀P₇₅K₇₅ kg/ha), F₂(N₂₀₀P₁₅₀K₁₅₀ kg/ha), and F3 (N₃₀₀P₂₂₅K₂₂₅ kg/ha). The results showed that plant spacing, NPK fertilizer, and their interaction significantly affected the growth and yield of broccoli. The highest yield per plant (331.42 g), yield per plot (8.29 kg), yield per hectare (13.81 t) at harvest were found in the spacing S₂ (60 cm x 40 cm) and highest yield per plant (344.78 g), yield per plot (7.95 kg), yield per hectare (13.25 t) was recorded when F₂(N₂₀₀P₁₅₀K₁₅₀ kg/ha) are used. The treatment combination S2F3 (60 cm × 40 cm with N₃₀₀P₂₂₅K₂₂₅ kg/ha) resulted in the highest plant height (63.27 cm), crown spread (70.20 cm), number of leaves (17), and length of the largest leaves (50.57 cm). For curd initiation, the treatment combination S2F2 (60 cm × 40 cm with N₂₀₀P₁₅₀K₁₅₀ kg/ha) required 54.33 days, with a primary curd weight of 0.48 kg and a curd diameter of 15.12 cm. Additionally, S2F2 resulted in a stem diameter of 4.02 cm, stem length of 26.73 cm, number of secondary curds (8.06), weight of secondary curds (78.99 g), fresh weight of leaves (401.49 g), yield per plant (365 g), and yield per plot (9.13 kg). The highest broccoli curd yield of 13.25 t/ha was obtained from the application of N₂₀₀P₁₅₀K₁₅₀ fertilizer, while the lowest yield of 9.36 t/ha was recorded with no NPK fertilizer. The yield of broccoli curd increased with decreasing plant spacing, with the highest yield of 13.81 t/ha from S₂(60 cm × 40 cm) and the lowest yield of 9.75 t/ha from S1 (60 cm × 50 cm) spacing. The best treatment combination was S₂F₂, resulting in a yield of 15.21 t/ha.