The yield response of King grass Pennisetum purpureum x P. americanum Burton, to an organic and urea fertilization was evaluated under and andosol at the departamento del Cauca, Colombia. The treatments with lime (O and 2 t of dolomitic lime/ha) showed no statistical difference. The highest dry forage yields for King grass were obtained with three t of hen-dung/ha/cut although there was no difference with urea (200 kg of N/ ha/cut). Nevertheless, quantities greater than 1 t of hen-dung/ha/cut and 50 kg of N/ha/cut are not recommended, since they showed the same behavior as to yield is concerned.