Flushing is a bad practice based on flawed science.

jumpincactus said:

with a lot, not all of the minerals and chemicals that fertilizer puts in the plant tissue and a large majority of these become "immobile" and or fixed in the plants tissue how than does flushing work?????

I call it the placebo effect. Stop using BS PGRs bud hardeners and a myriad of other junk then there wouldn't be a need to flush at all. But again I ask, with a lot of stuff the plant eats/utilizes becoming "fixed" in its tissues, how then does plain water remove it. Think about it brothers.

Click to expand...

I agree with you 100% I think it's the chlorophyll not the nutrients personally. Although ppl tend to think nitrogen is the culprit and that is mobile I have some evidence that disputes that and I can post once I get home. I have come this conclusion based on exclusion and studies I have researched and by no means am I the first one to do so. Not that I am qualified to say for certain but in my simple mind its likely.

Flushing has the possibility in aiding to break down the chlorophyll but the impact would depend on the drying process

jumpincactus said:

I call it the placebo effect. Stop using BS PGRs bud hardeners and a myriad of other junk then there wouldn't be a need to flush at all. But again I ask, with a lot of stuff the plant eats/utilizes becoming "fixed" in its tissues, how then does plain water remove it. Think about it brothers.

Click to expand...

Bacteria in the plant is all that will work on soil uptakes. How does water remove it? You can't flush Cannabis with water. Didn't know that was the debate. You flush with isotonic solution to block uptake of nutes over the period it takes the plants bacteria to do its job on the old. So that new material can't get in and the old can be broken down, by bacteria.

The problem is that isotonic solution has its own flavor.. By the time you need to flush, your bacteria is nil. Which makes the confusion worse since isotonic flushes are also bacteria feeds. Youve got a bunch of intent marketed to people with no understanding of how when where and why these circumstances actually benefit anyone. In most case they benefit the perpetual income on the hydro store

Quit thinking we're growing plants and just grow bacteria. We don't grow plants. We just fetch food. For bacteria. Curing has nothing to do with chlorophyll. If your crops have no bacteria and no plant sugars/fats etc, it gets confusing.

RippedTorn said:

Bacteria in the plant is all that will work on soil uptakes. How does water remove it? You can't flush Cannabis with water. Didn't know that was the debate. You flush with isotonic solution to block uptake of nutes over the period it takes the plants bacteria to do its job on the old. So that new material can't get in and the old can be broken down, by bacteria.

Quit thinking we're growing plants and just grow bacteria. We don't grow plants. We just fetch food. For bacteria. Curing has nothing to do with chlorophyll. If your crops have no bacteria and no plant sugars/fats etc, it gets confusing.

Click to expand...

all im getting at is I use organic inputs with a balanced living soil. Never flush and have never had any complaints on my meds. thats all Im sayn.

the topic was flush or not. I wasn't talking bacteria. I am well versed in soil science. So yes I am aware of the herd...…….. "Quorum Sensing" anyone :D

RippedTorn said:

Bacteria in the plant is all that will work on soil uptakes. How does water remove it? You can't flush Cannabis with water. Didn't know that was the debate. You flush with isotonic solution to block uptake of nutes over the period it takes the plants bacteria to do its job on the old. So that new material can't get in and the old can be broken down, by bacteria.

The problem is that isotonic solution has its own flavor.. By the time you need to flush, your bacteria is nil. Which makes the confusion worse since isotonic flushes are also bacteria feeds. Youve got a bunch of intent marketed to people with no understanding of how when where and why these circumstances actually benefit anyone. In most case they benefit the perpetual income on the hydro store

Quit thinking we're growing plants and just grow bacteria. We don't grow plants. We just fetch food. For bacteria. Curing has nothing to do with chlorophyll. If your crops have no bacteria and no plant sugars/fats etc, it gets confusing.

Click to expand...

This is so wrong idk where to start. Bacteria only permeate the roots (not all types) and depending on the bacteria have a symbiotic relationship by breaking nutrients down into a form more easily taken up by the plants. The plants provides food for the bacteria.

Aqua Man said:

I agree with you 100% I think it's the chlorophyll not the nutrients personally. Although ppl tend to think nitrogen is the culprit and that is mobile I have some evidence that disputes that and I can post once I get home. I have come this conclusion based on exclusion and studies I have researched and by no means am I the first one to do so. Not that I am qualified to say for certain but in my simple mind its likely.

Flushing has the possibility in aiding to break down the chlorophyll but the impact would depend on the drying process

Click to expand...

in my opinion there is no need for flush. Its all about careful selection of your inputs during the grow cycle and then a diligent and careful dry and cure process that produces a great tasting smooth smoke...……..

Aqua Man said:

This is so wrong idk where to start. Bacteria only permeate the roots (not all types) and depending on the bacteria have a symbiotic relationship by breaking nutrients down into a form more easily taken up by the plants. The plants provides food for the bacteria.

Click to expand...

ahhhhhhhhh I see you and I think alike. @RippedTorn while bacteria do play a huge part in living soil and great plant growth and cycling don't forget there are many other components that play key rolls in a healthy balanced living soil, nematodes, fungi and protozoa.

jumpincactus said:

in my opinion there is no need for flush. Its all about careful selection of your inputs during the grow cycle and then a diligent and careful dry and cure process that produces a great tasting smooth smoke...……..

Click to expand...

I fully agree, no flush here either.

Rootbound said:

I fully agree, no flush here either.

Click to expand...

GMTA :D

OK here is that study done very recently that supports flushing is not needed to reduce nutrient levels in cannabis. Its basically saying that there is no significant difference in nutrient levels between flushing and not flushing. However it did not test the levels of chlorophyll in the plants between flushing and not flushing. It also showed that flushing caused no negative effects on THC, yield, etc. Its a long read but you can pretty much skip to the conclusion unless you have questions on the methods of testing and conditions of growing.

After comparing more than a few papers, personal opinions and a shit ton of time reading on how plants processes actually work. IMO with no actual experience. I feel its the chlorophyll and not nutrients that are the culprit. Like I stated previously flushing may or may not help depending on the drying process. But interestingly enough I was kind of surprised that flushing had no negative effects and therefore no real reason not to. Flushing may also have positive/negative impacts on other factors like trichome production, terpenes and canabinoids. But that's another debate in itself.

Aqua Man said:

OK here is that study done very recently that supports flushing is not needed to reduce nutrient levels in cannabis. Its basically saying that there is no significant difference in nutrient levels between flushing and not flushing. However it did not test the levels of chlorophyll in the plants between flushing and not flushing. It also showed that flushing caused no negative effects on THC, yield, etc. Its a long read but you can pretty much skip to the conclusion unless you have questions on the methods of testing and conditions of growing.

After comparing more than a few papers, personal opinions and a shit ton of time reading on how plants processes actually work. IMO with no actual experience. I feel its the chlorophyll and not nutrients that are the culprit. Like I stated previously flushing may or may not help depending on the drying process. But interestingly enough I was kind of surprised that flushing had no negative effects and therefore no real reason not to. Flushing may also have positive/negative impacts on other factors like trichome production, terpenes and canabinoids. But that's another debate in itself.

Click to expand...

Great link. Few things jumped out at me who flowers that cold?? 20c is 68f. At days 11-44? That is cold. Cool temps reduce/influence nutrient uptake, reduce growth and encourage early ripening just odd they chose those temps. I would say the intended purpose of flushing is to improve flavor and burn quality. I get it tho what’s the mechanism for improved flavor, less nutrients in the bud? More terpenes? An even, complete combustion? Kind of hard to quantify flavor and taste, it’s very subjective. Idk. I’ll tell you this tho you’re not gonna win any competitions with unflushed weed; organic or not if you’re a heavy smoking connoisseur you can tell the difference. If you vape, pipe, bong make extracts, or eat it you likely will not notice a difference. If you smoke rolled joints heavily and you have a discerning pallet you will notice. Flush a plant and don’t flush one. Smoke a good ounce of each then make your decision. Anecdotal yes, but based on decades of trial and error by 1000s of growers

PharmHand said:

Great link. Few things jumped out at meView attachment 818909who flowers that cold?? 20c is 68f. At days 11-44? That is cold. Cool temps reduce/influence nutrient uptake, reduce growth and encourage early ripening just odd they chose those temps. View attachment 818908I would say the intended purpose of flushing is to improve flavor and burn quality. I get it tho what’s the mechanism for improved flavor, less nutrients in the bud? More terpenes? An even, complete combustion? Kind of hard to quantify flavor and taste, it’s very subjective. Idk. I’ll tell you this tho you’re not gonna win any competitions with unflushed weed; organic or not if you’re a heavy smoking connoisseur you can tell the difference. If you vape, pipe, bong make extracts, or eat it you likely will not notice a difference. If you smoke rolled joints heavily and you have a discerning pallet you will notice. Flush a plant and don’t flush one. Smoke a good ounce of each then make your decision. Anecdotal yes, but based on decades of trial and error by 1000s of growers

Click to expand...

Yeah I found that odd to but then you have to consider this was a production facility. I would assume their goals would be crop yield, turnover time and then quality. 1 thing i can say is they are using CMH lights that put aout a lot of UV so its likely the leaf temp would be much higher than the ambient temps.

Correction: I should probably think before responding. Leaf temps are almost always lower than ambient. I'm really not sure why they would use lower temps but maybe they know something we don't (or at least myself)

I agree flushing may absolutely affect trichome, terpens and cannabinoids. But apparently not nutrient content of the buds.

Aqua Man said:

OK here is that study done very recently that supports flushing is not needed to reduce nutrient levels in cannabis. Its basically saying that there is no significant difference in nutrient levels between flushing and not flushing. However it did not test the levels of chlorophyll in the plants between flushing and not flushing. It also showed that flushing caused no negative effects on THC, yield, etc. Its a long read but you can pretty much skip to the conclusion unless you have questions on the methods of testing and conditions of growing.

After comparing more than a few papers, personal opinions and a shit ton of time reading on how plants processes actually work. IMO with no actual experience. I feel its the chlorophyll and not nutrients that are the culprit. Like I stated previously flushing may or may not help depending on the drying process. But interestingly enough I was kind of surprised that flushing had no negative effects and therefore no real reason not to. Flushing may also have positive/negative impacts on other factors like trichome production, terpenes and canabinoids. But that's another debate in itself.

Click to expand...

Excellent paper!!!! thx for sharing this. :D

@UpInSmoke420
Like @PharmHand said there is not a lot of scientific studies on this but there is a lot of peer experience and opinions. I am not trying to prove anything one way or the other, only trying to understand and put together the possible science behind it to better understand what exactly is happening during flush, drying and curing. IMO with 0 experience I am inclined to believe that chlorophyll is responsible for the poor taste and dark ash. Not simply nitrogen as has been a popular though in the past. IMO flushing more than likely also plays a role in terpenes and cannabinoids and to an extent (that I have no idea) in the break down of chlorophyll. I think it would be less than most might think and I say that because chlorophyll contains nitrogen and this study is showing that the nitrogen levels are the same flush or not. Now whether or not the nitrogen in the test of this study is in the form of chlorophyll or other tissue I have no idea.

That is what I have based my opinion on. Proper drying and curing would have the most impact and flushing may aid slightly in breaking down the chlorophyll but also may increase terpene and cannabaniods. Also with no significant reduction in yield, THC etc. its only makes sense to me to flush for a few reasons. Save on fertalizer, may aid in the breakdown of chlorophyll and why not?

Now if its not chlorophyll that is responsible for this then just take what I have said and throw it in the trash. This is a really small part of the large picture.

OK I found a flaw in this study. The cannabis was dried and cured for 21 days before being sent for analysis. So it cannot determine whether or not the flushing had any impact on nutrient levels in the bud as this was done after drying and curing. In order to determine this they would need to send samples at the time of harvest and after drying and curing to show how much impact it had. Its possible at harvest the flushed buds contained much less chlorophyll but the drying process was enough to lower the amounts in both flushed and unflushed buds to almost identical levels. This would also support that drying and curing is the most important factor in the reduction of chlorophyll.

Please excuse my rambling as I am kind of posting as I try to figure this out and I hope its not pissing anyone off.

Aqua Man said:

OK I found a flaw in this study. The cannabis was dried and cured for 21 days before being sent for analysis. So it cannot determine whether or not the flushing had any impact on nutrient levels in the bud as this was done after drying and curing. In order to determine this they would need to send samples at the time of harvest and after drying and curing to show how much impact it had. Its possible at harvest the flushed buds contained much less chlorophyll but the drying process was enough to lower the amounts in both flushed and unflushed buds to almost identical levels. This would also support that drying and curing is the most important factor in the reduction of chlorophyll.

Please excuse my rambling as I am kind of posting as I try to figure this out and I hope its not pissing anyone off.

Click to expand...

If someone is offended by debate and learning they are in the wrong place:)

UpInSmoke420 said:

I won't lie, I got no idea what chlorophyll is, name sounds familiar kind of though. I replied to the first post not realizing there was 27 pages of replies lol. Figured my input might still apply though lol. I slightly understood what you meant but not fully, this stuff is a bit to technical for me right now lol.

Click to expand...

Chlorophyll is what makes plants green its what allows plants to absorb light energy.

PharmHand said:

If someone is offended by debate and learning they are in the wrong place:)

Click to expand...

I have been thinking about what you said with the lowered temps they used during this study. What I am wrestling with is lower temps would limit nutrient uptake to some degree, especially root zone temps. If the veg and flower phases were run with lower temps both rootzone and ambient temps than a typical grow room/s experience and nute uptake is limited, then would that in and of itself lend to better over final readings of accumulated nutrients in the flowers. Did that make sense? yea Im off work and baked...…… :D

jumpincactus said:

I have been thinking about what you said with the lowered temps they used during this study. What I am wrestling with is lower temps would limit nutrient uptake to some degree, especially root zone temps. If the veg and flower phases were run with lower temps both rootzone and ambient temps than a typical grow room/s experience and nute uptake is limited, then would that in and of itself lend to better over final readings of accumulated nutrients in the flowers. Did that make sense? yea Im off work and baked...…… :D

Click to expand...

Definitely. Lower temps ,less transpiration, less passive nutrient uptake and from what I understand and what I’ve seen in my veg room in the winter when it’s too cold phosphorus and iron uptake is reduced in cool root zone temps. When it’s really warm I cut my nute Ppms to account for the fact they’re transpiring so much therefore bringing up nutes passively at an accelerated pace. My veg room is 96f right now haha:)

Nice thread after all, i've losted all hopes in the first pages but, finally it turned fine with some real jewels.

A fews things hurt me, maybe to share it will help readers with the same grid of reading. Not a judgement but a feedback on the difficulty to read sometimes.

- The recurrent lack of context. It turn in a true conceptual comedy when an organic farmer fight with an hydro grower on the "flush" and the manner to understand it. With dick measurements.

- The quest of an universal, near unique, way to handle this problematic in all cases possible. Sound like the trick to win poker each round.

- Synthetic nutrients. I've never visited or encountered a single grower of ganja using this type of very expensive product. They are build at molecular level for a specific type of product (at gens sequence level), so on demand only and after a very expensive audit (because you don't have the right to use it anywhere, it's only for lab farms). Only to stock them in your farm will cost you more than to mount an entire grow op warehouse. WTF lol I guess it's a problematic of translation, i don't known.

To stay primitive on my point : organic is organic that's all, mineral : you need a mine, synthetic : you need a company than weight billions.

- The lack of "rinse sauce" recipes. Here we say "rinse" over "flush"(we use it more this last for toilets), but the concept is the same. When you begin and don't really understand what is in your bottles outside the feed chart of the company, the "plain water trick" and all its variations are the more natural way to begin in this game.

Near everybody started by this point before building personnal "rinse soups" that are more competitive in term of quality/yield. Trichome production increase, yield increase, anything increase ... by just a "flush" with plain water with sometimes quantity than make me think someone have builded a GMO aquatic cannabis in my back lol WTF bis. For one time we are speaking specially on quality only in this new paradigm of stabilized herms, ruderalis hybrids, and minute strains ...

I'm just very not compatible with this new "facebook way" to throw shit on others like primitive chimps, to determine wich one is the alpha. It sterilize the debate in sects saying always the same things in loops.

So thanks to HD wow to have mentionned in the flow a true existing "secret", even if no one give a fck about his critical share lmao

Since this thread started 5 yrs ago, almost to the day, I personally felt compelled to bump it or rekindle it. Especially since reading thru 27 plus pages visiting various linqz associated with the topic of "flushing".
Alright now, here is where I'll start. I consider myself to be a muthafkn GURU, a damn gro monsta, started off in hydro, dwc, soil mix, Coco mix, you name it I grew it ! Tons of strains and tons of Harvey's. Made some mistakes, rectified said mistakes. Met some marvelous people with loads of knowledge and willing to share some of the knowledge, met a bunch of a holes steering a MF in the wrong direction, which taught me to be diligent in my research. Also I read my bitches ( plants )
I know what they want n need ! But hell I'm still picking up pieces of this complex plant.

Now a far as flushing is concerned, that shit should happen throughout your grow, hell who doesn't like a refreshing drink a water, it should be done weekly followed by a light feeding . As for the finish, I prefer to use the term "final rinse" . Everyone should know by now to ramp your feedings down to a minimum towards the finish line. If done properly, that final rinse shouldn't take longer than 3 days. Think about it, after that final swell of them drippy resinous buds throw some of that plain old refreshing water. IMHO that'll take away the option of the roots to take in one last meal up to your finished product.

And to end this long ass diatribe, I'll mention drying and curing. As a must, drying should be done in the slowest manner possible, to me very important. You have to let the chemical process break it on down by itself, don't try n rush this process. Once the buds snap off of the main stem, clean it and begin next process after a sample of course ! Now if dried proper like, you should be able to enjoy a little. But not to much, put them shits in a mason jar almost packed but not stuffed. Give it a day or 2, and remove the buds inspect them shits, squeeze a little, smell em, if everything is how you put them in originally, put them back in the jar. Repeat this process for 2-3 more days, sample again, everything all good, put jars in a dark cool environment and forget about them for a few weeks, occasionally check on them. Once you get back to them you won't regret it, the flavor will have kicked in, and some of that sweetness. A little extra time and you'll never Eva purchase dispensary or black market bullshit again. Enjoy that finish product, roll up a fat jizzle and let that sizzle! And if you did this rite as your rollin up with fiskars in hand you should have some Stkyfingaz like ya boy !