Dear Dan, I have a question about flushing. I realize that when feeding synthetic chemical nutrients you must flush the salts, however, when growing organically, as far as flushing “nutes” from the soil, I’m really struggling to understand the point of this.
When growing organically, what would you be trying to “flush”? Microbes? I am basically running a fairly hot soil and feeding compost tea. Thanks for your input. – Kushyman
You should always flush your plants whether you grow using synthetic nutrients or organic ones. Both methods feed your plants with chemical elements, some of which need to be removed using the flushing process in order for your buds to burn properly, to a clean white ash. Organic nutrients derive these chemical elements from natural sources while synthetic plant foods are formulated in a laboratory from inert chemicals. Both build up in your plants and medium over the course of your grow cycle and the flushing process removes them.
For the last week or two of the flowering stage, use plain pH-balanced water and pour it through your medium at 3 times the volume of your containers (ie. 15 gallons of water for a 5-gallon bucket). After a few flushings, start testing the water that pours out from the container and you’ll see the ppm’s (parts-per-million) of your solution starting to go down. This is a good sign. Your fan leaves will also begin to fade in color but don’t be alarmed. This is another indication that your flush has worked.
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