Leeching vs Flushing

videoman

Leeching is done for a couple of reasons, first it can flush out excess salt and mineral buildup. Second is that it is useful for flushing out other organic waste products in the medium that are introduced by the roots and microrganisms. Third it can refresh stagnant voids in the medium(areas that are either wet or dry spots, or devoid of oxygen, deviant ph, etc).
Organic nutes are not as heavily derived from salts and thus that need is reduced however the other advantages still apply and perhaps more so since organic growing fosters a thriving herd of microorganisms in the medium, and ph flutuation is more common.
Pre Harvest Flush is usually cited as being necessary to use up or flush the mobile nutrients N,P,K,Mg and to restrict the immobile nutes resulting in a finished product with fewer chemicals resulting in a better quality smoke.
The key here is really not to create a difficiency of immobile or mobile nutes during the flush, thus the use of mollases, but instead to create a tapering off so that after 7-10 days the plant is right at the end of its resources for harvesting. Flushing too long and without supplying immobile nutrients can result in stunted finishin. Flushing is a good practice with both organic and chemy nutes. It takes practice to get the timing just right, and once again strains differ widely. If your plant is dark green at harvest you have probably not got it right, and if the leaves are all falling off you have probably gone too long.
In spite of the correct answer, the old addgae applies, if it ain't broke, don't fix it!

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