The OP is growing in coco. Coco is inert. If the OP has been feeding properly (not over feeding) then there is absolutely no reason to flush.
Measure the ppm of your nutes then feed. Then measure the ppm of your run off. If the runoff is higher then you need to lower your nute strength.
Since coco is inert, it needs nutes every time. If you feed with out nutes you are stressing the plant.
What if I only had water for 10 days? I would not be healthy.
I would like to add that if you flush soil (run gallons of water through your pots) you are crazy. Watering with plain water in soil is fine as there are nutes in the soil. Flushing away beneficial microbes and nutrients does not make any sense.
There is a big back and forth about flushing around here every time it gets brought up. Some say it is pointless and unscientific, and others hold the idea that it healthier and makes for a more tasty bud.
I'll always go with science over opinions. Please do not take offense at what I post, I think fundamentally we agree.
The answer will not be cut and dry but if you look at it a different way perhaps the decision to make becomes easy. I see no need for clear water only and no need for nutrients either in the final 5-10 days, so what to do?
He is growing in coco. Plants in coco need nutes to live. If he has been over feeding, then plain water the last 5-10 days might make the plant healthier.
There is plenty of food stored in the plant and the medium probably more than enough.
This is not true. Buds do not store nutrients. How could nutrients that are not there affect taste and smell?
To continue to fertilize might too be pointless/ wasteful, but I am of the theory that by tapering off nutrients and increasing runoff to 30%- 40% the root zone will purged more gradually and the plant will metabolize a more significant part of the remainder.
I agree that nutes should be tapered off in soil and hydro/coco. Again, if the OP didn't overfeed, flushing will be stressful and lower yield without raising quality. It could be argued that the quality will be lower since flushing in coco stresses the plant. I still do not understand why anyone would stress their plant on purpose.
In a Coco finish, I am done using most additives 14 days ahead of harvest and am where I began in terms of ppms. So with 2 weeks left, just decrease your nutrients by dilution, keep that ph right on and make that drain work. No plant stress, no wasted nutrients, no excess nutrients...by the end I am feeding @ 300 a/b/calmag....and the last watering is just tap.
Agreed. Measure the ppm of your nutes then feed. Then measure the ppm of your run off. If the runoff is higher then you need to lower your nute strength.
One of the problems of the flushing debate is there are many definitions. Plain water the last day will not hurt and that is not really flushing. Watering coco with plain water the last 10-14 days is just crazy to me.
I am about 2 weeks from picking. I have been feeding with R/O water, calmag and GH nutes at about 450 ppm. I will mix up a batch today that is a little lower, about 300 ppm.
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Unrelated opinion about organic/coco
I have been growing in coco for about 3 years now. It is great but it is too much work. I'm going back to organic soil.
With organic soil, you do almost all the work ahead of time. You get a great soil mix and that is it. You can just water the plants with tap water. No ph, no ppm, no dicking around. If you want to feed more, just mix up a batch of tea. It is too easy.
After watching a friend's organic soil plants grow as fast as my coco plants with much less effort, I am going back to organic soil.
With coco I feed every day. With soil I will be watering about every 2-4 days.
I am pretty amazed at how easy organic soil is and wonder why more people do not do it.
I'm not doing it so I can say shit like, "My weed is organic, brah." I'm doing it to simplify my growing and reduce the amount of time spent working on my plants.