Effect of the Combination of Compound NPK Fertiliser and Potassium Fertiliser on the Growth and Yield of Bawang Dayak (Eleutherine palmifolia (L.) Merr.)

Abstract

Bawang Dayak (Eleutherine palmifolia (L.) Merr.) is a bulbous plant with cultivation potential; however, its productivity is influenced by nutrient availability and appropriate fertilisation management. This study was conducted to identify the best combination of NPK 16:16:16 compound fertiliser and potassium fertiliser for improving the growth and yield of Bawang dayak, with particular emphasis on bulb diameter as an important indicator of yield quality. The experiment was conducted at the Integrated Agricultural Zone, Medan Baru, Muara Bangkahulu District, Bengkulu City, Bengkulu Province, Indonesia, from October 2025 to February 2026. A completely randomised design with one factor was used, consisting of six fertiliser treatments: no fertiliser, 2.5 g NPK plant⁻¹, 1.25 g NPK plant⁻¹ + 1 g potassium plant⁻¹, 1.25 g NPK plant⁻¹ + 2 g potassium plant⁻¹, 0.62 g NPK plant⁻¹ + 1 g potassium plant⁻¹, and 0.62 g NPK plant⁻¹ + 2 g potassium plant⁻¹. Each treatment was replicated four times, with five plants per experimental unit. The observed variables included plant height, number of leaves, number of tillers, leaf greenness, time to flower emergence, fresh plant weight, bulb fresh weight, number of bulbs per clump, bulb diameter, and root fresh weight. Data were analysed using analysis of variance at the 5% significance level, followed by Duncan’s Multiple Range Test when treatment effects were significant. The fertiliser treatments significantly affected plant height, bulb fresh weight, and number of bulbs per clump, but did not significantly affect number of leaves, number of tillers, leaf greenness, time to flower emergence, fresh plant weight, bulb diameter, or root fresh weight. The 2.5 g NPK plant⁻¹ treatment produced the greatest plant height and bulb fresh weight, while 1.25 g NPK plant⁻¹ + 1 g potassium plant⁻¹ produced the highest number of bulbs per clump.