Professional grade Potting Mix
I want to make all purpose potting mix with coco peat, vermiculite and PBH (parboiled rice huls). Can I add Osmocote to this mix. Is osmocote enough or should I add any other nutrients? If so, how much I should add for a 25 lbs of soileless growing medium as said above?
If NOT Osmocote, what should I add for NPK fertilizer and in what quantities? Thank you in advance for your help.