Hey Rebecca, can you specify what you mean by "flush"? Different growers call it different names. I don't flush at all, but I'd like to understand your method.
Hey Rebecca, can you specify what you mean by "flush"? Different growers call it different names. I don't flush at all, but I'd like to understand your method.
Sure @conradino! In the final stages of a grow, I stop using any nutrients in my water when I water my plants. I take a reading of the parts per million of the particulates in the water going in. I use a dissolved solids meter to measure this.
Then, I keep flushing water through the plants until the water draining out of each pot comes within 100 parts per million of the water that I originally went in.
This is done to remove fertilizers and nutrients before harvest.
Not everyone does this though... I do this because residues (fertilizers/nutrients) can be toxic especially if/ when the final product is lit on fire to be smoked or high heat is used in baking.
I'm using this plant as medicine and I need it to be as clean as it can be...not only that it directly affects the flavour too and I want my produce to be as good as my 2 hands can produce. LOL!
Ok I understand, you basically try to leach the nutrients by pouring bulk amounts of water into the soil. But do you know exactly which ones are running off? To my knowledge electrically neutral current of water will take the excess of anions (mostly nitrates and sulphur) and calcium and magnesium with it as these bind weaker to soil particles... and not much more really.
The problem is that plant needs everything till the end of flowering (including nitrogen, which is a building block for proteins) and that "flushing" has detrimental effect on microbial and fungal population in soil as it basically cuts off the supply of oxygen, thus promoting anaerobic bacteria.
Also while a lot of nitrates will be flushed, the first reaction of the root system to abundance of water will be their absorption as these are very mobile, which is why a boost in growth is often noticed... new leaves, news pistils etc.
I personally grow LOS/High Brix style, where "flushing" is never applied and produce is as delicate and tasty as it gets, but I always try to find out what is the reason for the growers to "flush" in soil.
This is a very interesting topic @conradino23. Thanks for starting the conversation! Hopefully more people will contribute to the discussion. Admittedly, I don’t know anything about the growing style that you have referenced but I will do some research so that I can learn. :)