As far as flushing goes, there are several misconceptions about flushing in the cannabis world that personally I do not consider to be true, I’ll deal with compost/soil as this is what we are talking about here.. In the cannabis world the term is used to cover several different things. Years ago in the cannabis world the term was exclusively used to refer to dealing with removing an excess of chemicals/minerals from compost/soil after an excess of fertiliser had been applied, by running several times the volume of water through the compost to remove the excess chemical salts.
This works where chemical salt fertilisers have been used and a large overdose has been fed in the short term. Say a 10 litre pot of compost by running 20 to 50 litres of pure water through it would save a plant where it had by mistake been fed double or triple the maximum dose, as long as done before the plant wilted down to much.
Where it does not work so well, is where slightly high chemical fertiliser doses have been used over a long period until the salts have been absorbed my the humus above saturation point and started crystallising in hard salt forms some of these are pretty toxic, start killing roots and can not be washed out of compost in the short term.
Anyhow the using the term flushing under the above circumstances is pretty much correct I think and in line with general horticultural termsused today.
Over the last ten years or so the the term flushing has started to be bastardised as a term in the cannabis world. Referring to removing elements from a plant via the roots into the compost by just using water for the last week or two and believing this happens. It does not happen as far as N
:K is concerned, roots of plants do excrete various chemical some even work as complex weed killers inhibiting other plants growing close by, but not as fertiliser salts back into the soil, well not until the roots start dying/rotting and becoming part of the humus mass.
So the term flushing as far as removing chemical from the plant by just using water in the last week or two of a plants life may well be an incorrect term to use, if you equate:- to flush, to = to drive out or to wash out with a large volume of water. When as has been said what actually happens is in fact the plant is starved of nutrition and is forced to metabolise any internal excess and then past that into leaching from the leaves to try and complete its life cycle ie: finish flowering and make provision to reproduce its self.
Ps my water sits at around 8, but I ph to 6.5-6.8
