Effect of a Mixture of Leaf Waste and Ash with a Bioactivator on Compost Characteristics and Corn Growth

This study aimed to analyze the characteristics of ash from waste combustion, the quality of compost made from leaf waste, ash, and various bioactivators, as well as their effects on corn growth. The research was conducted in two stages. The first stage focused on compost production using two factors: the proportion of leaf waste and ash (A0: 0% ash, A1: 5%, A2: 10%, A3: 15%, A4: 20%) and the type of bioactivator (B0: none, B1: EM4, B2: Stardec, B3: straw isolate, B4: Trichoderma). The second stage tested the resulting compost on corn plants using a completely randomized design with one factor and three replications. Data were analyzed using analysis of variance (5%) and the Duncan test (5%). The results showed that the combustion ash had varying qualities: the pH, NPK, Ca, Fe, and Zn contents met quality standards, while the organic carbon content was below the standard, and the C/N ratio exceeded it. Heavy metal Hg levels were below the limit, but Pb and Cd exceeded quality standards. The compost produced from a mixture of leaf litter, ash, and bioactivators also varied, with its pH, organic carbon, and total N+P+K content meeting the Indonesian National Standard (SNI) for organic fertilizer; however, the nitrogen and phosphorus contents were below the SNI requirements. Regarding corn growth, the highest plant height was observed in treatments with 5% ash and the Stardec bioactivator. In contrast, the lowest height was observed in compost without ash and with the Trichoderma bioactivator.