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Coffee Treatment Results

  • #21
Sorry guys. Have to put the coffee thing to bed. Caffeine, theobromine, and several other secondary metabolites of Coffee are allelopathic to other plants. These are found in the seeds as well as leaves, which inhibit seed germination and root growth in many other plants. Whether this is specifically active upon Nepenthes is up for debate.

However, I suspect that you will find as the concentration of caffeine and other compounds rises, growth of your plants is inhibited.

http://link.springer.com/article/10.1007/BF00987675#page-1
http://link.springer.com/article/10.1007/BF00167865#page-2
 
  • #22
Sorry guys. Have to put the coffee thing to bed. Caffeine, theobromine, and several other secondary metabolites of Coffee are allelopathic to other plants. These are found in the seeds as well as leaves, which inhibit seed germination and root growth in many other plants. Whether this is specifically active upon Nepenthes is up for debate.

However, I suspect that you will find as the concentration of caffeine and other compounds rises, growth of your plants is inhibited.

http://link.springer.com/article/10.1007/BF00987675#page-1
http://link.springer.com/article/10.1007/BF00167865#page-2

So basically it temporarily gives a growth spurt, but over time will start to slow the plant down?
 
  • #23
I suspected this would get myth-busted eventually. Thanks Kevin.
 
  • #24
I suspected this would get myth-busted eventually. Thanks Kevin.
C'mon Paul, admit it! You've been searching all along for outside justification for bogarting all that good coffee!:-D
 
  • #26
I appreciate the useful links, theplantman, but the context of that study does not necessarily translate to the fertilization of these specific plants. I've witnessed firsthand examples of coffee fertilization improving both growth and fruit output on various acid-loving plants, such as blueberries, grapes, Nepenthes, and particularly Sphagnum. In one case, a 25 year old grape tree nearly doubled its fruit output compared to all previous years after just one season of coffee treatment.

It's amusing that people will jump to the conclusion that the results presented by many of us over the seasons are simply "myths," especially when some of those people have careers in this very field, after simply glancing at the abstracts of two papers that do not point specifically to that being true. Try it for yourself and see if it works. I've done year on year off treatments with and without coffee and there is a difference, whether from re-acidification or otherwise. These were concentrated extracts, not diluted, drinkable coffee. Generally I appreciate cynicism, but let's go through the entire study, especially the materials and methods, before we proclaim to now know the truth because of a couple of abstracts. And this might sound arrogant as hell to some people, but with all due respect, I have to assume the majority of members here don't even know what it is they're reading in those studies, as it's not something you can simply jump into. It's not uncommon for peer-reviewed studies to be fraught with problems or inconsistencies when trying to apply the results to similar problems, and it takes reading them thoroughly, several times, with a meticulous eye, to really grasp what was conducted.

And with all that being said, I appreciate the links and debate in general. If there are more studies out there to substantiate the claims that the allelopathic compounds found in coffee outweigh the effects of those compounds that may be beneficial to plants, I'll definitely be keeping an eye out for them.
 
  • #28
I appreciate the useful links, theplantman, but the context of that study does not necessarily translate to the fertilization of these specific plants. I've witnessed firsthand examples of coffee fertilization improving both growth and fruit output on various acid-loving plants, such as blueberries, grapes, Nepenthes, and particularly Sphagnum. In one case, a 25 year old grape tree nearly doubled its fruit output compared to all previous years after just one season of coffee treatment.

It's amusing that people will jump to the conclusion that the results presented by many of us over the seasons are simply "myths," especially when some of those people have careers in this very field, after simply glancing at the abstracts of two papers that do not point specifically to that being true. Try it for yourself and see if it works. I've done year on year off treatments with and without coffee and there is a difference, whether from re-acidification or otherwise. These were concentrated extracts, not diluted, drinkable coffee. Generally I appreciate cynicism, but let's go through the entire study, especially the materials and methods, before we proclaim to now know the truth because of a couple of abstracts. And this might sound arrogant as hell to some people, but with all due respect, I have to assume the majority of members here don't even know what it is they're reading in those studies, as it's not something you can simply jump into. It's not uncommon for peer-reviewed studies to be fraught with problems or inconsistencies when trying to apply the results to similar problems, and it takes reading them thoroughly, several times, with a meticulous eye, to really grasp what was conducted.

And with all that being said, I appreciate the links and debate in general. If there are more studies out there to substantiate the claims that the allelopathic compounds found in coffee outweigh the effects of those compounds that may be beneficial to plants, I'll definitely be keeping an eye out for them.
1) What makes you certain that of the dozens of chemical constituents in coffee grounds, the acidity is the only principle causing the "good effects" you describe?
1a) Couldn't the same be said for any pH-lowering acid, like lemon juice or vinegar?
2a) Have you tested the pH regularly the entire time you have "tested" coffee?
3a) Is there any evidence that coffee nutritionally benefits plants?

2) What traits did you measure to assess growth? Have you quantified the net output of leaves, fruit, and overall health (leaf nutrient analysis, soil analysis) in any of the plants to which you have applied coffee?
2a) Do you have control groups?
2b) Did you quantify the levels of coffee-derived chemicals you were applying to your test plants?

3)The studies I pointed out (keep in mind I could have done further research, but easily found supporting evidence in ~15 minutes) broke the coffee plant into most of its constituent chemicals. In the first study, almost all of coffee's secondary metabolites inhibited other plants.
3a) This evidence is corroborated with empirical evidence from coffee plantations, which (1) have been around for quite awhile and (2) show allelopathy toward competing plants. I consider that significant long-term experience.
3b) What I'm saying is that the majority of scientific evidence points to the hypothesis that high levels of coffee derivatives would most likely have negative impacts upon other plants. If there is comparable scientific evidence asserting positive effects from caffeine, theobromine, tannins, or anything else, then by all means, we should bring it to the table for discussion.

4) I resent the assumption that others are incapable of reading scientific papers. I won't go into detail, but there are people in the world that work in the field of plant science. I'm not going to spend hundreds of dollars buying scientific journals to show what is to me an obvious conclusion.
 
  • #29
theplantman, I think what mato is trying to say is that while these articles demonstrated the allelopathic effects of coffee towards ryegrass, fescue, and lettuce, it is simply too broad of a statement to say that the same is true for Nepenthes and all other species, and certainly doesn't
put the coffee thing to bed. ]
, at least for carnivorous plants. I think it is important that people try for themselves and see what works and what doesn't. Obviously some people on here have had great results and others haven't.
 
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  • #31
First of all, let me say that none of this was directed at you specifically, especially not what I said about reading scientific papers, as I'm already aware of what you do for a living. You seem to have taken it that way, particularly by ending your post the way you did. But I will ask you this, do you think people who have never read a scientific paper or have any background knowledge of these subjects are going to simply comprehend what was written in the way that was intended? Even if they "get the gist of it," the assumption that it holds up under these specific circumstances is simply one that can't be made. The entire paper has to be read for more than just the results of the abstract. There are too many variables in these two studies to assume we are all just imagining that it works.

But to circumvent a debate that I'm not about to have, many growers have used coffee treatments and found evidence that it works. For some plants, no, it doesn't do much, but for Nepenthes and a few others, it works very well. This is all qualitative, as nobody here (at least, not me) cares enough to run a formal experiment in order to disprove it. I'm not going to run statistical analyses, spend months of my life, and petition to use lab resources on this. But you definitely could, since you do work in a greenhouse where I'm sure space for control plants is ample. In fact, I'd love to see it. Maybe you could even have undergrads do the tedious work for you. And, you already seem to have the questions laid out nicely.

Again, I'd rather not go down your list, but my comments on acidification were not really worded in a way that would allow you to assume that this is what I feel is causing the "good effects." I feel that it may have something to do with it, but I never said this is solely what causes it, nor would I be so presumptuous as to pretend to know.

I appreciate the studies, I found them very informative, and I'm not saying they're wrong, but saying you have to "put this coffee thing to bed" comes off as a specious statement when considering the diversity of the plant kingdom. I doubt even the authors of those two papers would try to assert that compounds found in coffee would have definitive allelopathic effects on all plant life, especially those that are not even closely related to the test plants, at least to the point of noticeably inhibiting their growth.
 
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  • #32
Im not really going to say if its definitely working or not working, however I know that my plants up until now have been displaying consistent steady growth, in a consistent environment. Within the week of giving them coffee they have all exhibited growth spurts. The sphagnum has also gone completely insane in my pots and is beginning to overgrow some of the Nepenthes. I find it hard to believe this is purely coincidental, as nothing else in their environment has changed.
 
  • #33
ScreenShot2014-11-18at55627PM_zps9e3dd50f.png



Hindsight Bias
http://psychology.about.com/od/hindex/g/hindsight-bias.htm
 
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  • #34
First of all, let me say that none of this was directed at you specifically, especially not what I said about reading scientific papers, as I'm already aware of what you do for a living. You seem to have taken it that way, particularly by ending your post the way you did. But I will ask you this, do you think people who have never read a scientific paper or have any background knowledge of these subjects are going to simply comprehend what was written in the way that was intended? Even if they "get the gist of it," the assumption that it holds up under these specific circumstances is simply one that can't be made. The entire paper has to be read for more than just the results of the abstract. There are too many variables in these two studies to assume we are all just imagining that it works, which is an insinuation that I don't appreciate. Also, if you work in a university greenhouse, why would you need to pay anything for these papers?

But to circumvent a debate that I'm not about to have, many growers have used coffee treatments and found evidence that it works. For some plants, no, it doesn't do much, but for Nepenthes and a few others, it works very well. This is all qualitative, as nobody here (at least, not me) cares enough to run a formal experiment in order to disprove it. I'm not going to run statistical analyses, spend months of my life, and petition to use lab resources on this. But you definitely could, since you do work in a greenhouse where I'm sure space for control plants is ample. In fact, I'd love to see it. Maybe you could even have undergrads do the tedious work for you. And, you already seem to have the questions laid out nicely.

Again, I'd rather not go down your list, but my comments on acidification were not really worded in a way that would allow you to assume that this is what I feel is causing the "good effects." I feel that it may have something to do with it, but I never said this is solely what causes it, nor would I be so presumptuous as to pretend to know.

I appreciate the studies, I found them very informative, and I'm not saying they're wrong, but saying you have to "put this coffee thing to bed" comes off as a specious statement when considering the diversity of the plant kingdom. I doubt even the authors of those two papers would try to assert that compounds found in coffee would have definitive allelopathic effects on all plant life, especially those that are not even closely related to the test plants, at least to the point of noticeably inhibiting their growth.

I definitely agree that scientific literacy is nowhere near universal. Scientists, the media, and the public are all to blame for that, and it's a frustrating issue. Furthermore, knowing many scientists and future scientists personally, I can attest that they are flawed human beings that cut corners. There are hastily rushed or poorly constructed experiments out there simply because there is significant pressure to get grants, keep jobs, or graduate. You are right that scientific papers aren't (nor should they be) the law of the land. Conversely, science shouldn't be dismissed because of the bad apples out there producing junk science.

However, what I noticed is this. There are studies out there about allelopathy, but not in the use of coffee as a source for improving plant growth. And of course, for Neps this is an unstudied area. But if I had to bet money on whether coffee would likely inhibit the growth of any random plant, I would bet that it would. Simply because that has already been shown. If none of the secondary chemicals help plant growth, then essentially all we can safely say is that coffee adds slight levels of nutrients. Same as any other composted plant product.

I am likewise only interested in debate if it can produce real answers. Probably best to wait for the people with space, time, and money to pursue things like this. I personally believe there is a great need for research into specific horticultural issues for rare and endangered plants. Fact of the matter is, like you said, it takes money and time and manpower. Getting funding for such research is unlikely. Our Sarracenia lab gets a fraction of the funding that goes toward crop plants. Unfortunately, in research the horticulturists are just the "yes" men. The researchers--and their grant money--set up the questions to answer and the plants to look into. We're just there to make crazy ideas work, and hopefully become better horticulturists in the process.

That being said, allelopathy and plant competition fascinates me to no end. I would welcome the day someone approached me about injecting caffeine into plants to see what happens.
 
  • #35
I agree and appreciate this thoughtful response.
 
  • #36
Hey guys, I'd just like to say that my University library provides subscriptions to hundreds of scientific journals, as well as historic information via newspapers, magazines, and pretty much everything you can think of.

As long as you guys are using it for purely educational purposes, I'd be happy to either pull up a full-text article you can't see on the normal web, or briefly search on a subject you guys are curious about.

I can't link them obviously, but I can let you download them.
 
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