Hey Conradino - do you think there are other reasons why it might be beneficial to flush besides the "cleansing the buds" theory (I agree with you that there's no point in cleansing the buds of an organic grow, by the way). The taste argument aside, I think a flush does help clear any salts that may have developed around the roots, and if you couple a flush with lowered temps you stress the plant out and can trigger that final, desperation push of development as she tries with all her might to attract pollen.
However, I'm a hydro grower, not an organic grower, so maybe I have no idea what I'm talking about Always good to learn something I don't know. Appreciate your insight.
I wonder how the flush with just water came about. I guess through simplicity, a desire to wash out the hydro medium (in organic I agree it is completely silly). But in hydro it has always seemed like too drastic a measure. We go from feeding plants full on to replacing the nutrient rich liquid in the soil with plain water. The osmotic difference is huge. The plant goes from a banquet to starvation. Now think about this. We often are fine with many nutrients at the end of flower (phosphorus, potassium,etc) but many nutrients may be on the verge of deficiency (nitrogen, magnesium, etc). So yes flushing the soil may remove a lot of salts but then feeding with straight water is going to invite these deficiencies to go from borderline to critical. Water is also not efficient at removing "locked" up nutrients in the soil.
I take an alternate approach in hydro and soilless. During the height of flower I am giving them about 2/3 the recommended amount of nutes. Then when the last two weeks arrive I flush not with water but 400ppm nutes drain to waste. This helps unlock and carry away salts. It also leaves the soil with a mild nutrient solution. This encourages the plant to use up the nutrients it has stored because we are not feeding it enough to survive. But the low strength nutes help counteract any deficiencies and let the plant complete its bulk up phase and increase terpenes and trichomes. The very last watering I use just water but that is just a convenience and saving nutrient thing. Then I let the soil dry out and the plant just have a hair of wilt before cutting the plant. The increased dehydration is supposed to help with trichomes. Believe me the bud comes out just as smooth if not smoother because it had a gentle decline to harvest instead of full on starvation. Taste is improved as well.
Soon I won't have to worry as I will be all High Brix!