Optimizing The Growth of Microgreen Broccoli (Brassica oleracea) Using a Combination of Top Soil and Rice Husk Charcoal

Broccoli microgreens (Brassica oleracea) are highly nutritious functional vegetables that require optimal growing media to support their growth. This study aimed to evaluate the effects of different growing media on the growth and nutrient content of broccoli microgreens. The research was conducted from October 8 to November 1, 2023, at a home garden in Perumahan Tasbih, Medan, with chlorophyll, protein, and flavonoid analyses performed at the Biotechnology Laboratory, Faculty of Agriculture, Universitas Sumatera Utara, Medan. The study employed a non-factorial randomized block design with three types of growing media: control (topsoil), topsoil + 15% rice husk charcoal, and topsoil + 30% rice husk charcoal, each with nine replications. Parameters measured included plant height, fresh weight, and the content of protein, flavonoids, and chlorophyll (chlorophyll a, chlorophyll b, and total chlorophyll). The results showed that variations in growing media significantly affected the growth and nutrient content of broccoli microgreens. The topsoil + 15% rice husk charcoal medium produced the highest chlorophyll and protein content, while the topsoil + 30% rice husk charcoal medium resulted in the highest flavonoid content. These findings indicate that combining topsoil with rice husk charcoal can optimize the nutritional quality and growth of broccoli microgreens.