Flushing Cannabis Before Harvest (When)??

OK, been @ this for a tad overt a year & truly need advice on "Flushing" the plant towards the end. I read a bunch on using the various solutions & in our wonderful democracy/republic we have the God given right to pick & choose which one is best. No problem there, just need to know which works best with an outdoor grow & when to apply. Again, read all different times when to use a "flush"? Anyone out there with some good solid advice?

Sic Semper Tyrannus

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