Angelica Sono, Langimanapa Sofia Demmassabu, Pemmy Tumewu, Jantje Pongoh, Jeanne M. Paulus, Stella Tulung
Growing media are one of the main components in plant cultivation, both conventional and modern, functioning as a medium for root growth and development, as well as providing nutrients, water, and air required for plant metabolism. This study aimed to determine the effect of growing media and to identify the best growing medium for the growth and yield of green mustard (Brassica juncea L.). This study was conducted in Kakaskasen Dua Village, North Tomohon District, Tomohon City, at an altitude of 800 meters above sea level. The research was carried out from October to December 2025 with a single-factor Completely Randomized Design (CRD) with five growing media treatments, namely soil (M0), soil : chicken manure (1:1) (M1), soil : chicken manure : rice husk charcoal (2:2:1) (M2), soil : rice husk charcoal (1:1) (M3), and soil : chicken manure : rice husk : rice husk charcoal (1:1:1:1) (M4), each replicated five times. The observed variables included plant height, number of leaves, and fresh weight of the plant. Data were analyzed using analysis of variance (ANOVA), followed by the Least Significant Difference (LSD) test at the 5% level. The results showed that treatment M2 produced the best growth (plant height of 44.72 cm and number of leaves of 16.60) as well as the highest fresh weight yield of green mustard. Keywords: growing media, growth, mustard greens, rice husk charcoal, yield