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Is the coffee as fertilizer debate settled?

Seen some post about nepenthes being fertilized by coffee and big leaf jump. This reminded me of a huge long post I read before about how some folks think it's not effective and in some cases bad for the plant.

Any update on this subject? thanks
 
You're wanting a black and white answer to a subject that is in shades of gray.

Effective fertilization can only occur when the plant uses each nutrient to the fullest. Too much or too little of any one component can cause problems.
Too little of an nutrient will obviously have a negative effect on plant growth, but so will too much.
Excess of one element may prevent the uptake of another, proper fertilization is a balance of many macro and micro nutrients

If I use coffee and my plants need what coffee offers than I see a boost in growth. If I use coffee but my substrate already supplies all the plant can handle of a certain element than I will see the application of coffee as doing harm.

There is no one right answer to this,
 
I keep reading this too, same question XD
 
Settled for me. No reason to use mumbo jumbo when there are products out there that do a substantially better job of growing plants. Fertilizer mixes are developed and tested for that sole purpose.

Think of how many commercial nurseries you know that use artificial fertilizers. Then think of how many use coffee, or compost tea, or unicorn horns.
 
Settled for me. No reason to use mumbo jumbo when there are products out there that do a substantially better job of growing plants. Fertilizer mixes are developed and tested for that sole purpose.

Think of how many commercial nurseries you know that use artificial fertilizers. Then think of how many use coffee, or compost tea, or unicorn horns.

There is no "mumbo jumbo" to be had. There are over one thousand active chemical compounds within coffee; and whether plants simply benefit from further acidification of their media; whether more significant chemical reactions occur, it has proven beneficial in my experience. Coffee is particularly high in phenolic compounds -- some twelve percent of dry weight in unroasted beans -- which have a role in breaking down decaying plant material; thereby, freeing up some complex organic nutrients.

As far as commercial nurseries are concerned, the local one here not only uses and sells compost "teas" but also brings in spent grounds from Starbucks and Peets by the wheelbarrow load, to add to their composts . . .
 
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There is no "jumbo jumbo" to be had. There are over one thousand active chemical compounds within coffee; and whether plants simply benefit from further acidification of their media; whether more significant chemical reaction occur, it has proven beneficial in my experience. As far as commercial nurseries are concerned, my local one not only uses and sells compost "teas" but also brings in spent grounds from Starbucks and Peets by the wheelbarrow load, to add to their composts . . .

Experiencing a local shortage of unicorn horn?:D
 
  • #10
Maybe some biosymbiotic (is that a word?) benefits as well..... just a thought.
I've read that some large golf courses spread corn meal on their greens to increase Trichoderma growth.
Evidently some species go ape when fed a little corn meal.

but way out of my league now, I'll let you bio major types play
I got crayons :)
 
  • #11
I've read a little about this topic in the forum, and it is pretty interesting that some people "see" positive effects.

Here is a study showing that incorporating spent coffee ground has physiological effects on Lettuce. They observed increased carotenoid and chlorophyll concentrations. Biomass generally decreased with more coffee in the soil (the abstract is a bit misleading because increased biomass in 10% coffee treatment is not statistically supported if you read the full text). They interpret that the plants get stressed with addition of coffee, and caused the increased pigment concentrations (which is good for human who eat them).
http://www.mdpi.com/1420-3049/17/2/1535

Caffeine has been shown to have some phytotoxicicity. Generally, in several plants, root growth gets suppressed with caffeine. I had to read about it because I was going to use caffeine powder to control bush snails.

https://bibliotecadigital.ipb.pt/bitstream/10198/8720/1/23 Artigo Ativ Enzimática Cong Madrid.pdf

http://link.springer.com/article/10.1007/s11738-007-0132-4 (abstract only)

Now, this doesn't mean that it doesn't work for CP. Somethings could be generalized to plants, but others may be specific to each group of plant species. Also, spent ground is different from extracted coffee.
 
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  • #12
It seems to me that the so-called "debate" is not whether coffee treatments have something to offer or not, but how well they measure up against commercially formulated fertilizers. Does coffee add nutrients to the soil that appear to be beneficial to Nepenthes? Yes, it appears so. Does coffee do a better job than commercially formulated fertilizers? Absolutely not, IMO.

I did coffee only for a year and saw a reduction in performance of my adult plants. When I resumed fertilizing with a balanced Orchid blend fertilizer (Dyna Gro Orchid), plants looked better, leaves grew larger and pitchers increased in size. I don't bother with coffee anymore.
 
  • #13
It seems to me that the so-called "debate" is not whether coffee treatments have something to offer or not, but how well they measure up against commercially formulated fertilizers. Does coffee add nutrients to the soil that appear to be beneficial to Nepenthes? Yes, it appears so. Does coffee do a better job than commercially formulated fertilizers? Absolutely not, IMO.

I did coffee only for a year and saw a reduction in performance of my adult plants. When I resumed fertilizing with a balanced Orchid blend fertilizer (Dyna Gro Orchid), plants looked better, leaves grew larger and pitchers increased in size. I don't bother with coffee anymore.
Caffeine started getting to you?
 
  • #14
Caffeine started getting to you?

LOL
Let me rephrase that - "I applied coffee-only to my plants for a year, etc. etc" Better?

PS: How much caffeine is there in Unicorn Horn, anyway?? :-O
 
  • #15
LOL
Let me rephrase that - "I applied coffee-only to my plants for a year, etc. etc" Better?

PS: How much caffeine is there in Unicorn Horn, anyway?? :-O
Too much. I use the decaf.
 
  • #16
There is no "mumbo jumbo" to be had. There are over one thousand active chemical compounds within coffee; and whether plants simply benefit from further acidification of their media; whether more significant chemical reactions occur, it has proven beneficial in my experience. Coffee is particularly high in phenolic compounds -- some twelve percent of dry weight in unroasted beans -- which have a role in breaking down decaying plant material; thereby, freeing up some complex organic nutrients.

As far as commercial nurseries are concerned, the local one here not only uses and sells compost "teas" but also brings in spent grounds from Starbucks and Peets by the wheelbarrow load, to add to their composts . . .
Let me set the record straight. I'm not claiming there are absolutely no benefits to coffee-derived media supplements. Perhaps in the short term it does create a "boost" of sorts. While the chemistry is, as you mentioned, complicated, there is a consistently high presence of a chemical (caffeine) which has demonstratably allelopathic properties. Thus, regardless of what other chemicals are in coffee-based additives, at the end of the day they're attached to caffeine, and this is always a downside. Jury's still out if this specifically impacts Nepenthes and other CPs.

Now, when you compare this to fertilizers, the benefits of coffee derivatives are negligible and probably harmful in the long-term. If a plant is starving, adding almost anything in the world with minimal amounts of N-P-K would improve them. Having a substantial amount of experience with fertilization regimens for a vast diversity of CPs and non-CPs, I'd never choose coffee over fertilizer. Furthermore, most of the nurserymen and horticulturists I know would follow suit, especially if they were tasked to grow plants quickly and at a dependable rate.

It isn't that coffee doesn't work at all. It's like Paul seconded: it's a lackluster solution to achieve greater, healthier plant growth. And therefore in my opinion, it's an obsolete idea that isn't productive to play with anymore. Let's say a person is early into this hobby and wondering how to improve the health/vigor of their plants as well as expand their horticultural skillset. Assuredly, the payoff is higher if that person spends time experimenting with fertilizers and not coffee.
 
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  • #17
Coffee is particularly high in phenolic compounds -- some twelve percent of dry weight in unroasted beans -- which have a role in breaking down decaying plant material; thereby, freeing up some complex organic nutrients.

As far as commercial nurseries are concerned, the local one here not only uses and sells compost "teas" but also brings in spent grounds from Starbucks and Peets by the wheelbarrow load, to add to their composts . . .

Aren't many phenolic compounds volatile? The roasting process would remove the volatile compounds.

The operative word here is "compost". Composting releases or transforms the nutrients in the "compost materials" so they can be utilized by the plants. The primary nutrient being nitrogen. All the literature I've read about using coffee as a fertilizer refer to using the grounds which are a good source of nitrogen as it breaks down.

It isn't that coffee doesn't work at all. It's like Paul seconded: it's a lackluster solution to achieve greater, healthier plant growth. And therefore in my opinion, it's an obsolete idea that isn't productive to play with anymore. Let's say a person is early into this hobby and wondering how to improve the health/vigor of their plants as well as expand their horticultural skillset. Assuredly, the payoff is higher to spend time experimenting with fertilizers over coffee.

There is also the cost if you are using just the brew - if you look up the cost per gallon for coffee you'll see estimates from $0.50 to $100 per gallon. Assuming you get some low-cost brand like Folger's the cost per gallon ranges from around $0.50 to $0.75. I estimated that with a fertilizer like MaxSea the cost is about $0.05-$0.20 per gallon depending on what strength you use.
 
  • #18
Analysis of spent coffee ground (from the lettuce paper):

N 1.2%
P 0.02%
K 0.35%
Mg 0.1%
Caffeine 0.18%

N is slightly higher than typical peat-based potting soil, but P K Mg isn't higher. Also all N is in organic form (immobilized), so it isn't immediately available. Some epiphytes can directly absorb some amino acid. Indeed in a Brazilian study of some orchids, it has shown that inorganic (chemical) fertilizer + organic fertilizer did better than the case when they were used separately. So nutritional content is very small. Actually, in the lettuce study, N-content from the leaf analysis shows that N concentration in the leaf decreases with more coffee in the soil.

Additionally, caffeine can influence some soil microbes because it is toxic to microbes and plants, and it can influence the microbe fauna. This could have negative or positive effects to the potted plants.
 
  • #19
Analysis of spent coffee ground (from the lettuce paper):

N 1.2%
P 0.02%
K 0.35%
Mg 0.1%
Caffeine 0.18%

Useful information, to be sure. But the "Nepenthes coffee treatment" doesn't involve spent grounds, it employs brewed coffee, as if you were making it for your own consumption (however, for use on plants, it gets diluted significantly).
 
  • #20
I just "coffee'd" my plants after reading this. I hadn't done so in a long time. Typically, it's something I do once a year or so, while relying on fertilizer every two months or thereabouts (it used to be every two weeks, but I get lazier the longer I grow these things).

In the past, I've been part of this debate, using plant physiology jargon as well as firsthand experience to make my case. However, the topic has acquired the scent of a bloated, decaying horse (for me, anyway). That being said, David (Big Bella) has eloquently summed up why many of us use coffee in as concise a description as I could imagine, and he has done so in numerous posts over the years. Regarding my experience with this form of supplemental nutrients, I do notice improved growth in certain plants, whether some species simply metabolize these compounds more effectively, appreciate the acidity, or perhaps are benefiting because of the media they're in - I'm not entirely sure. I have noticed that species found naturally in serpentine soils benefit conspicuously more from this than others, but again, I'm not sure why, and perhaps the results won't be the same for others who follow suit.

As a note for new growers who are curious about trying this nutrient regimen, I will say that it doesn't harm the plants, which is something that can occur when inexperienced growers decide to "experiment" with synthetic fertilizers. But as with any nutrients introduced into a contained substrate, flushing is always recommended to improve airflow and reduce growth of unwelcome guests. This applies to both coffee and synthetic fertilizers.

I'll probably continue to use both synthetic fertilizer (Grow More urea-free or Maxsea all purpose) and coffee for the foreseeable future, but I don't put too much stock into it these days. There are factors in the environment that I have more trouble maintaining than nutrients, such as temperature, root space, light, humidity, pests, etc.. All of which have profound effects on the health and growth rate of these plants. It's often recommended that you should only supplement nutrients once your plants are already healthy, as you will be able to gauge how much, or how little, is needed (as Butch (Av8tor) touched upon above). In addition, these application rates further depend on factors such as temperature, light, media, moisture,, CO2 availability, etc., which are all limiting factors in almost the same way nutrients are limiting factors.

A pretty good rule of thumb for those "new" growers reading this now or years from now: Make sure your thumb is green before you purport to have one.
 
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