They really are.
Flush or not to Flush?
- Thread starter Oh Canada!
- Start date
MadBret
Member
I guess I'm not actually flushing but just watering with plain water for the last week or two. Appreciate the detailed explanation, bud. Take care.Been a while since I shared in one of these threads so I figured I would.
Until the last few years flushing always referred to "running large amounts (3x the container volume was often recommended) through your medium to remove nutrients, some people even suggested doing it multiple times. That is still the definition when talking about fixing a nutrient issue or salt buildup. However in the last 5ish, maybe 7 years some people have tried to change the definition to avoid flushing debates, or because as they learned the science and realized that pouring massive amounts of water through your medium wasn't helpful but they still had to justify their cognitive dissonance. Flushing is not the same as watering with plain water or watering with lighter nutrients.
Since I typed this all out already I might as well make my stance clear on the subject. I've done multiple side-by-sides with clones in the same environment where flushing was the only difference. I've mostly grown in hydro, but have done some soil runs as well, and I have grown well over a thousand plants at this point of many different genetics. I understand the process of how plants uptake and USE nutrients to grow. I don't flush plants at harvest, it's pointless. There have also been material analysis tests done that prove there is no significant difference in the molecular make up of flushed plants vs unflushed plants.
Flushing is only used for correcting a severe nutrient issue in the medium. Flushing a plant can absolutely damage the root system and stress the plant delaying growth so it should only be done if really necessary.
Tapering feed down at the end and watering according to the plants needs won't hurt anything at all, and promotes a healthy plant all the way to harvest. Using only water the actual last week or 2 won't hurt, but that's not flushing that's just called watering. The other issue is many many many growers(even experienced ones) don't seem to understand when the plant is actually in those last 2 weeks. In which case if you cut out nutrients too early you will loose out on something in the end, either yield or quality depending on the situation.
Grow your garden however you want to, its your garden. But the best buds come from healthy plants that are grown until they are fully ripe and then dried properly to ensure a quality smoke.
I've been using advanced nutrients for awhile with mostly great results and their feed charts recommend flushing the last week. I'm beginning to suspect this is because the feed charts lean toward overfeeding. Scientific research shows no noticeable difference between flushed or not. Then again, lab grown research weed is unlikely to be overfed. Currently running 2 different auto strains here on the same nute schedule. One started looking sick. Flushed the pots and the sick one had high nutrient concentration while the other one was fine. Different plants have different appetites. IMO flushing is probably the best route unless know your nutrition is dialed in spot on. Going forward I'm thinking maybe it's better to cut nutes down and watch for deficiency rather than deal with toxicity. Still learning here. Long story short flushing is probably best for novice or intermediate growers and not necessary for the master level.
Edit. Just to be clear. By flushing in the end stage I'm speaking of simply deprivation of nutes in the last week or so. Only water. Unless plants are already underfed, there are still some nutes in the soil. End flushing is merely avoiding piling more nutes on top of existing. Not to be confused with flushing the pot with copious amounts of water for the purpose of leaching or rinsing the soil of excessive or toxic levels of nutrients and salts.
Edit. Just to be clear. By flushing in the end stage I'm speaking of simply deprivation of nutes in the last week or so. Only water. Unless plants are already underfed, there are still some nutes in the soil. End flushing is merely avoiding piling more nutes on top of existing. Not to be confused with flushing the pot with copious amounts of water for the purpose of leaching or rinsing the soil of excessive or toxic levels of nutrients and salts.
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Relaxed
Well-Known Member
i have a bunch of experience now. stop listening to everything nut companies try an sell you. If you are organic just water normal without nuts the last couple waters for me is 2 weeks. The flushing meaning drown the plants with 2 or 3 times normal water is plain dumb. you shock the plant of what it enjoyed during a grow. NOBODY flushes tomatoes and they eat them all day long. These are plants. I know life long growers of vegis for sale at farmers markets. They do not flush our food. Dont flush or you are stressing it out at life cycle end of an annual not needed. Ignore this if you use non organic cause I wouldnt play that game.
coreywebster
Well-Known Member
Considering a huge number on here are legal and have the ability to have their merchandise tested it would be great if we could all do a go fund me or something and nominate two growers who would be happy running a side by side each with same strain and parameters so we can put this to bed and make the whole thing transparent and sticky it.
I mean , I know there's a few articles shared on the subject but not by verified independent parties.
So who better to do it but us, here!
I'd happily stick a couple of hundred quid into the costs associated.
Then we can refer anyone asking directly to that thread and delete the weekly questions.
I mean , I know there's a few articles shared on the subject but not by verified independent parties.
So who better to do it but us, here!
I'd happily stick a couple of hundred quid into the costs associated.
Then we can refer anyone asking directly to that thread and delete the weekly questions.
Bud man 43
Well-Known Member
Not to flush- feed all the way till the end
Thing is outside plants may experience the temps dropping to the point that certain nutrients are locked out like below 15c and are then unavailable for uptake think like autumn conditions sure it is probably not the case with tomatoes but this is something few consider with cannabis and with flushing your somewhat trying to mimic that fade effect more than drown the medium either way flush dont flush its you whos smoking it at the end of the day i dont get why this debate continues to the point of arguments every flushing thread or question ends the same way on forums ime people never gonna agree
And Op my advice is try a wee test flush half your crop dont flush the other dry n cure properly see what bud you prefer
J. Rocket
Well-Known Member
I've had the feed/irrigation pump come on while harvesting a plant. 
If you "flush" for weeks you have chosen the harvest date well in advance.
IMO much better off letting the plant tell you when its ready.
Typically I'm not sure of the harvest date until I'm within a couple/few days of it.
If you "flush" for weeks you have chosen the harvest date well in advance.
IMO much better off letting the plant tell you when its ready.
Typically I'm not sure of the harvest date until I'm within a couple/few days of it.
Oh Canada!
Well-Known Member
5 Godfather OG and 1 purple punch
secretmicrogrow420
Well-Known Member
in my opinion there's not need to flush if you know what you're doing if your a professional. but for scrubs like me we gotta flush lol cuz we feed synthetic salt based ferts super heavy until chop so if i dont flush my end product will be wrecked. lol
Oh Canada!
Well-Known Member
Not sure if I totally know what I'm doing. But they look healthy so will continue to feed.
Hope I don't fuck this up.
Thundercat
Well-Known Member
That isn't how plants work. You can't take out what you already put into them.
There is nothing wrong with "salt based nutrients" they are the exact same IONS that are absorbed from organic soil. If you are feeding super heavy that is your actual problem.
EDIT: Also as such a new inexperienced grower you should really stop giving out advice like you have any idea what you are talking about. I constantly see you spouting nonsense "because you and your brother" did something.
Scuzzman
Well-Known Member
plain and simple people- Flushing is not required , BRO RUBBISH- if you think you need to do this its a you problem not a plant problem -you caused it by trying to force feed to grow the special fire that all those you tubers/forum gods(Newbies/uninformed) talk about....
Kola_Kreator
Well-Known Member
Vader OG gives a detailed explanation for his reasons for flushing before harvest at 17:21 of this clip.
Kola_Kreator
Well-Known Member
He does understand the plant science which backs up his opinion.
Thundercat
Well-Known Member
If he thinks flushing at harvest does anything beneficial NO HE DOES NOT UNDERSTAND THE PLANT SCIENCE. Cannabis is not a magical plant that is totally different than others. He is literally making stuff up as he goes along and making it sound scientific. He is suggesting using "sweeteners" lmao.
He says in the beginning he isn't familiar with the studies. Well the GreenRX study alone has proven that there is no significant difference in the chemical make up of flushed weed vs non flushed. So his theory is just wrong.
Thundercat
Well-Known Member
I did watch the video and edited my post appropriately.
Kola_Kreator
Well-Known Member
The GreenRX study does not look at the levels of the B vitamins. Vader's theory and understanding of the plant science specifically related to B vitamin levels.