Hi Thor.
I don't flush my grows as it is organic. are your girls outside, if so, i would start using it now for the three times, and then check it in four weeks and see if you need to do it again. I am betting you won't, but i don't know your conditions.
I am so very happy still with this product. I want to use it again, but haven't found any need to...wow. love this stuff
Green mojo to you.