... the customer's specific requirements. 23-21-0+4S npk fertilizerN.P.K. (23:21:0 + 4S)COMPLEX FERTILIZER NPK 23 ... the most important are:NPK 30-9-9, 13-13-21, 11-22-16, 12-12-17+2MGO, 27-6- ... 0 + S, 16-20-0 + S, 20-10-0, 23-21 + 4S, 23-23-0,NK compound fertilizers 10-0-8 ... , 10-0-10, 16-0-2, 19-0-19, 21-0-21, 22-0-19, 18-0-27, 25-0-19 ... , 21-0-24PK compound fertilizers 0-20-20, 0-10-10 ...