You could use mg 15-30-15 for the entire grow if you like the results were great for me!,but as of latley I have been using 10-52-10 for flowering and the buds were really great as well,as long as you keep a high ph during flowering things should work out...as for using a higher PH product should be used when starting your flowering cycle,say in canada around august the 15th or so,the 15th is just a mark set up could be a little sooner or a little later.....note:alot of people say Miracle grow is the shits! but I disagree havent had alot of problems with their product other then a bit of fert burn from time to time,but thats because their product has alot of good shit in there!................................good luck...............and remember there are probably a dozen people or more will disagree with me,but based on my own grows only................besides wouldn't try to lead you astray lol after all it's important to all of us here that you grow some great bud!...good luck and hope I have been some help..