I found this on my computer yesterday while looking for something else and it's worth a look I think. Going to give it a try for sure next time I flower some out. Have no idea who the author is.
"A concern for all cannabis growers is to prevent mineral and fertilizer build-up in ripened buds. We often speak of “rinsing” the plants of their accumulated nutrient salts before harvesting. This process is not actually able to pull mineral nutrients out of the plant, but instead we aim to starve the plants during the last few weeks of blooming.
By withdrawing all mineral fertilizer from the root zone, either by leaching the soil with water or by chemically locking some nutrients out of solution with Epson salts (“Rinsing” chemicals), we want the final 2 weeks of growth to rely on the plant’s own internal reserves.
By growing without mineral salts, the final buds will have reduced amounts of nitrogen and phosphorus, two macronutrients known to accumulate at the growing ends of shoots. Buds with higher levels of these mineral nutrients are less aromatically flavoured, they dry “greener” and sometimes will not vaporize as well at lower temperatures. We want to dilute the mineral tissue content by growing with just water.
A way to super-charge the rinsing stage is to enhance the uptake of water by cutting ripe plants 7-10 days before harvest and then placing them in pure water. These rootless plants are treated like cut flowers from the florist that live in a vase, and they will be able to uptake much more water than when attached to their root systems. This happens since water will move up the stem by “capillary action”, which is faster than when the plant is attached to roots. In this case however, the “vase” should be a large bucket of water that is replaced everyday.
By continuing to grow the cut-stem-plants under full light and CO2 in dry air for 7-10 days, they will “drink” much more water. All the grower needs to do is replace and replenish the water everyday; they will transpire amazing amounts of water and the growth of the ripening phase will more rapidly dilute all minerals in the shoots, much more than when plants are left to ripen on their root systems.
When ripening cannabis plants this way, the green pigments suddenly fade while yellow, orange and purple pigments become prominent. Cut-stem cannabis plants placed in fresh water transpire and grow for up to 2 weeks if provided with a good growing environment, they have large internal reserves to use up for growth and are programmed to finish the ripening process with a last surge of cellular expansion.
Trichomes are the last cells to grow and mature on cannabis plants, but all living cells will use the increased flow of fresh water up the cut plant stem. Growers could also add a water soluble fragrance or essence such as vanilla extract to the water and discover how to enhance the bouquet and flavour of the dried buds."