when should i switch to bloom?

yo, i've been using grow for a while now (IONIC) and the plants have been flowering for about a week, perhaps more. when should i switch to grow, and then when should i add bloom?

plants are AF, growing in soil/perlite/vermiculite.

cheers!

grow for veg, bloom for flower. stop using all nutes a week before harvest and just use water.

if they are flowering use bloom now