Growth and yield of yardlong bean (Vigna unguiculata subsp. sesquipedalis) applied with organic fertilizer

The study evaluated the effects of different organic fertilizers on the growth, yield, and soil health of yardlong bean (Vigna unguiculata subsp. sesquipedalis) under field conditions at the Institute of Agricultural Technology, Isabela State University, Cauayan Campus. The experiment was arranged in a randomized complete block design with four treatments: control (no fertilizer), compost, vermicompost, and organic manure, each applied at 10 t ha⁻¹ and replicated three times. Growth parameters, yield and yield components, and selected soil health indicators were measured during the growing period and after harvest. Results showed that organic fertilizer application significantly enhanced vegetative growth compared to the control. At 8 weeks after planting, compost- and vermicompost-treated plants attained greater heights (45.5 and 47.3 cm, respectively) than the control (35.8 cm). These treatments also produced higher leaf numbers and thicker stems. Yield performance was markedly improved under organic fertilization. Compost recorded the highest pod yield (5.40 kg plot⁻¹ and 0.35 kg plant⁻¹), longest pods (75.30 cm), and greatest number of pods per plant (8.50), followed closely by vermicompost, while the control produced the lowest values. Soil health parameters were positively influenced by organic amendments. Compost increased soil organic matter from 1.20% in the control to 3.50%, raised soil pH from 5.20 to 6.20, and improved nitrogen (0.22%) and phosphorus (18.50 ppm) levels after harvest. Overall, the findings demonstrate that compost and vermicompost are effective organic nutrient sources for improving growth, yield, and soil health of yardlong bean, supporting their use in sustainable production system.