Homemade Ferts???

noob grower...have closet grow 5 grandaddy prp vegg'n under 400W HPS....I read that grass clippings and pretty much any other green plants will create a true organic nitrogen solution when soaked in water for a month....all these diff expensive ferts and nutrients with all kinds of names is overwhelming..I've tried MG blood meal 12-0-0 burned my plants as well as some slow release fert spikes..also i'd like 2 know if anyone has had luck composting any help is greatly appreciated :rastasmoke: