I give plain water for the last 7-10 days. So does every grower I know, and that's personally dozens of growers in my neighborhood. I have had pot that burns black ash and goes out a lot, mostly from Hydro grows that haven't flushed properly, but I've also had promix grown pot that is harsh and burns black too. Maybe from over feeding, not sure.

But my reasoning for plain water the last week or so is simple; promix has a cation exchange capacity. It's not inert and holds on to nutrients to a degree, which it can release to the plants if needed. It's why I can get away with multiple water only feedings mid cycle before seeing deficiencies. By giving just water at the end the plants can use up what little they need from the stored cation bank, or from the leaves. Essentially they just dont need a lot of input the last week or two.. maybe a little potassium sulphate, but that's it.

Now I'll freely admit I have no science to back this up, just anecdotal evidence.

Hydro and coco are a different story. You should feed those what they need to within days of the chop. But any media with a CEC should have plenty of stored nutrients to make the last week or two without feeding added nutes.

Dirtbag said:

I give plain water for the last 7-10 days. So does every grower I know, and that's personally dozens of growers in my neighborhood. I have had pot that burns black ash and goes out a lot, mostly from Hydro grows that haven't flushed properly, but I've also had promix grown pot that is harsh and burns black too. Maybe from over feeding, not sure.

But my reasoning for plain water the last week or so is simple; promix has a cation exchange capacity. It's not inert and holds on to nutrients to a degree, which it can release to the plants if needed. It's why I can get away with multiple water only feedings mid cycle before seeing deficiencies. By giving just water at the end the plants can use up what little they need from the stored cation bank, or from the leaves. Essentially they just dont need a lot of input the last week or two.. maybe a little potassium sulphate, but that's it.

Now I'll freely admit I have no science to back this up, just anecdotal evidence.

Hydro and coco are a different story. You should feed those what they need to within days of the chop. But any media with a CEC should have plenty of stored nutrients to make the last week or two without feeding added nutes.

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Depends on how heavy you fertilize. Heavily faded plants do not give the best quality or yield in my opinion.

But overfed plants are not good either.

MIMedGrower said:

Depends on how heavy you fertilize. Heavily faded plants do not give the best quality or yield in my opinion.

But overfed plants are not good either.

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Totally. finding the sweet spot wrt to feeding and fading is what sets good growers apart from amateurs imho.

Flush too early, bad for the plants. Feed to much too late, bad for the plants. There is a happy medium.

Ikkt said:

Think about molasses, has a lot K and Ca iirc. No wonder you can give a shit load of it till the end without problems, perhaps even benefits.

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I'm half convinced the the biggest help that molasses provides is that it gives guys something to do to their plants that isn't fatal. ;-)

OldManRiver said:

I'm half convinced the the biggest help that molasses provides is that it gives guys something to do to their plants that isn't fatal. ;-)

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that made me laugh.. and I agree.

I think you have read different papers from myself:-)

What?

Overdose a plant on molasses and see what happens.

RippedTorn said:

Overdose a plant on molasses and see what happens.

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They turn into sugar junkies and lose all drive and ambition.... Next thing you know, they’re stealing from you.... They all either end up dead, or in the pen. The life of a molasses user is typically short and brutal- they make pretty corpses. So sad

PharmHand said:

They turn into sugar junkies and lose all drive and ambition.... Next thing you know, they’re stealing from you.... They all either end up dead, or in the pen. The life of a molasses user is typically short and brutal- they make pretty corpses. So sad

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But I do love me a molasses-whore. MMMMM

OldManRiver said:

But I do love me a molasses-whore. MMMMM

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Me too. I think it’s the lack of teeth.

Ahhh. Sugar sluts. Sweet!

I've got a little story for ya. My friend who grows in coco and rockwool had a bad last harvest. His weed tasted pretty decent and there were some aspects of it that I really liked initally. But after exhale I would feel too much irritation in my lungs. After a few hits my lungs would hurt so bad I wouldn't be able to smoke any more and I would be coughing without even smoking anymore. I have noticed this phenomenon before on a few occasions since I have been smoking weed now for 34 years. I don't know what causes it and hopefully someone here knows and will chime in. My theory is that there is somehow too much sulfur bound up in the flowers. This comes from when I was young and dumber and a friend showed me how to take match hits. You light a match and imediately inhale while it is lighting up and you will blow out a cloud of smoke. After a couple of those you have a hard time breathing like when you smoke this weed my friend grew. Anyway I asked him what he thought happened and he said he didn't flush good enough. I told him I'm pretty sure that is not what happened and if he doesn't change something about how he grows he is going to end up with the same problem no matter how much he flushes. He was adamant that he was correct. He uses the GH trio and likes to change the ratios around really radically. I think that is where he went wrong as well as the fact that he went the whole grow with no runoff. My last run I decided to chop at day 44 so I could get to the next run that I'm really excited about and the 44 day run had a couple of clones that I have already discontinued because I don't care for the taste, so I chopped with no flush at all, but I had already ramped the nutrients down to around 500 from my high of 900. (I use ro water) Like I said it was a spur of the moment decision so no flush at all. My friend was sure that I would have the same harsh smoke that he did. His mind was blown when he smoked my 44 day no flush weed and it tasted good! Obviously it wasn't the best smoke I've grown and I won't be doing it that way again any time soon, but I have definately smoked a lot of way worse weed! I think the light bulb lit in my friend's head too as now he has decided to change his techniques and try organic top dress coco style. (I still use hydro salts, but have recently switched to powdered nutes to save $)

Glow said:

I think you have read different papers from myself:)

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You said you'd have a study, cannabis specific, that shows our nice little trees are doing nearly nothing the last weeks and posted a study.
I can't find anything that could lead to such conclusion in the Chandra et Al. Study.

So if you're talking about the Chandra study could you please point out where I missed or misunderstood something?
Or if you're talking about another study could you please provide a link or name?

I think it's not just me who would like to learn more about what's happening at the end of the life cycle, seems interesting!

PharmHand said:

They turn into sugar junkies and lose all drive and ambition.... Next thing you know, they’re stealing from you.... They all either end up dead, or in the pen. The life of a molasses user is typically short and brutal- they make pretty corpses. So sad

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Faces of Molasses. It's a scary thing. Poor ladies.

Farmer P said:

I've got a little story for ya. My friend who grows in coco and rockwool had a bad last harvest. His weed tasted pretty decent and there were some aspects of it that I really liked initally. But after exhale I would feel too much irritation in my lungs. After a few hits my lungs would hurt so bad I wouldn't be able to smoke any more and I would be coughing without even smoking anymore. I have noticed this phenomenon before on a few occasions since I have been smoking weed now for 34 years. I don't know what causes it and hopefully someone here knows and will chime in. My theory is that there is somehow too much sulfur bound up in the flowers. This comes from when I was young and dumber and a friend showed me how to take match hits. You light a match and imediately inhale while it is lighting up and you will blow out a cloud of smoke. After a couple of those you have a hard time breathing like when you smoke this weed my friend grew. Anyway I asked him what he thought happened and he said he didn't flush good enough. I told him I'm pretty sure that is not what happened and if he doesn't change something about how he grows he is going to end up with the same problem no matter how much he flushes. He was adamant that he was correct. He uses the GH trio and likes to change the ratios around really radically. I think that is where he went wrong as well as the fact that he went the whole grow with no runoff. My last run I decided to chop at day 44 so I could get to the next run that I'm really excited about and the 44 day run had a couple of clones that I have already discontinued because I don't care for the taste, so I chopped with no flush at all, but I had already ramped the nutrients down to around 500 from my high of 900. (I use ro water) Like I said it was a spur of the moment decision so no flush at all. My friend was sure that I would have the same harsh smoke that he did. His mind was blown when he smoked my 44 day no flush weed and it tasted good! Obviously it wasn't the best smoke I've grown and I won't be doing it that way again any time soon, but I have definately smoked a lot of way worse weed! I think the light bulb lit in my friend's head too as now he has decided to change his techniques and try organic top dress coco style. (I still use hydro salts, but have recently switched to powdered nutes to save $)

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I just tried my one month old harvest which I never flushed and fed right to the end. I didn't cough even a single time and there was different strains in that grow. Your friend maybe overfed with one or more nutrients and/or didn't dry properly the end product.

Yeah, it's way more complicated than just flushing!

My only bad burning harvest was kind of flushed to death and burned black and sooty. Just disgusting.

You need to take a look at tobacco. There are a lot of studies!
High potassium and Calcium make a clean white/grey Ash. Black Ash is from poor soils with low mineral content.
But with our herb there is definitely some more to it. I have the suspicion that the composition and moisture content of the resin is important too, not just the plant matter.
In some cases the resin or the whole bud can even get hygroscopic, Wtf?!

My point is it's not just flushing and those people claiming to taste the difference from ten feet away while jumping from a plane with their eyes pried out, a burned tongue and a cut off nose are just victims of their own confirmational bias, didn't grow the pot well, f*cked something else up or missed another relevant factor
If flushing would be the main factor organic and outdoor pot would always taste quite bad cause it always gets fed right up to the chop.

I envy you guys over there, you can just send in samples, if you're willing to shell out the money, and get hard data. I hope it won't take long till I can do that, if the data helps to make conclusions or just opens up more questions and confusion is in fact another thing...

Ikkt said:

If flushing would be the main factor organic and outdoor pot would always taste quite bad cause it always gets fed right up to the chop.

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They would tell you that somehow let's say organic phosphorous is somehow different than the phosphorous in a chemical fertilizer and that's why the organic doesn't need flushing.

Ikkt said:

If flushing would be the main factor organic and outdoor pot would always taste quite bad cause it always gets fed right up to the chop.

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Not necessarily true. As the temps in the soil cool outside microbial action slows down and converts less of the organic matter to nutrition for the plants.

"Yeah, I mean, you know, it's like chemicals, right!?!
Wouldn't touch your toxic chem buds with a ten feet pole while enjoying my McDonald's burger!"
;)

I'm in no way opposed to organic farming and growing, I think it's a great way to raise crops and takes a lot of skill to really master. And most don't. I for sure don't.
That it works using an abundance of organic material or "organic" minerals doesn't mean you're in control and know what you are doing. And it for sure doesn't put you on some moral high ground.

Things like claiming mineral nutrients (often coming from the same source and being refined) contain more toxic heavy metals, acting like organics like for example guano would generally be environmentally beneficial/better or organic weed wouldn't need a flush because organic and the like i.e. putting any common sense by side is what bothers me.
Many of those people are on the cutting edge of our post factual times and don't care for any reason or logic. They're reluctant to further their knowledge if it doesn't fit their emotions and cemented views.
Perhaps one of the most serious problems and challenges of our times.

Not that all or most organic growers are like that but things like organics, esoterics, wild conspiracy theories or anti scientific views attract certain kinds of people that among other characteristics care more about what feels right to them than what's actually true.
And that's exactly what separates growers as I've seen here and on other boards often.
It's not organic vs. mineral or soil vs. hydro. Why should it be?
It's honestly caring about facts, furthering knowledge even if it painfully collides with our views and accepting there are different roads to Rome vs. just accepting what feels good and fits ones view and acting like yours is the only acceptable way.
With the first everybody comes along but the second often only come along among each other.

@MidwestToker
Right, that's true outdoors in certain climates and with plants with a certain flowering time. But that would be exactly what a Knowledgeable grower does with mineral fertilizer. And it is gradually less, it isn't abruptly nearly nothing!
Btw. outdoors there is the potential to grow real full organic, with worms and insects and rotting matter and pooping in a trench some years before planting and burying whole fish and and and and.
If I had a greenhouse I'd have one half hydroponic and one half organic for sure.
I'd really like that very much!
As I said, I'm not opposed to organics, I'm opposed to felt truth, claims to sole representation of the one and only truth/method and just being an unreasonable ***** with cemented views!

And sorry for the not really on topic ranting, smoked the first time after a break and got quite some logorrhoea...