when i use high n bat guano mexican to be exact i only use it twice myself. i mix a good amount as a top dressing for my soil say almost double the recomended dose and just blend it in the first two inches.even though i use more than advised it never hurts and acts as a slower releasing fert for a couple months. and once i see the first preflowers i give them a dose at recomended levels mixed with water. this has never hurt my plants and i see a differance between those that get it and those that dont. its good for your plants and soil. if youve got some fert sensitive plants dont give them more than recomended this year im growing some autos and i see they dont like as much nitrogen so im going low on them. i also use water soluble ferts along with the guano feeding low levels of ferts as needed.