Effect of Coffee Grounds as a Bio-Input in Lettuce Cultivation

Coffee grounds can be used in agriculture as a bio-input to enhance soil fertility and biodiversity in the long term, particularly in vegetable production. This study aimed to identify the effects of coffee grounds on the growth and yield of iceberg lettuce plants. The experiment was conducted in a greenhouse using 4 kg of substrate in containers with a 5 kg capacity, following a completely randomized design in a 2×2 factorial arrangement. The primary treatment consisted of plants grown in two types of substrate: soil and sand (01) and soil, sand, and 10% coffee grounds (02). The secondary treatment corresponded to irrigation with water (01) and a 10% coffee ground extract solution (02). Direct incorporation of coffee grounds into the soil reduced lettuce growth and should not be used without prior treatment. Under these conditions, soil fertility increased, with higher macronutrients and organic matter levels. Irrigation with a solution containing coffee grounds showed promise due to its high potential as an agricultural bio-input for lettuce production. This solution promoted plant growth and development, producing vigorous plants with market value.