Honestly, don't bother. Flushing doesn't create a better smoother smoke. The reason for harsh smoke isnt nutes in the bud, it is the chlorophyll. Flushing doesn't break down the chlorophyll in the buds. Only doing a proper slow dry and cure will do that. If you flush you are just starving and stressing your plants for no gain. Think about it, the plant will cannibalize its leaves to get the nutes to build its buds. That means whether you feed it or not nutes still end up being deposited into the buds.