Granular fertilizer normally is put down prior to planting and lightly scuffed into the dirt. It can go on several days or longer in advance of planting day. If you are broadcasting your seed, you can put the fert down at the same time, and scuff it all under at once. If you are using liquid fertilizers, they can be sprayed onto emerging plants. It is not really a good plan to put granular fert down after planting and just leave it lay on top of the dirt. Good luck.