my 2 cents advice - find out if there are farmers around where your farm is who are in this biz. When u do that,get the contacts of the exporter/s and pay them a visit. Most exporters usually give farmers seeds and will tell you what fertilizer and pesticides to use - how and when. Check out the link below but if it doesn't open,google it up and see the many different exporters and what products they deal with.
http://www.fpeak.org/