I have access to an almost unlimited supply of coffee grounds and can't help wonder if it could somehow be put to good use growing weed. I've read lots of anecdotal articles about how great it is as an amendment as well as some scientifically back articles about how you should avoid it unless you can fully decaffeinate it (caffeine, it seems, evolved as a natural herbicide to block competing plants). Coco bricks ain't particularly cheap though and coffee grounds are on the acidic side which is good for where I live where everything is high pH. Anybody actually try using it as a main component?
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Coffee grounds as a medium. Anyone try it?
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True if properly composted coffee grounds have good things in them, however they also contain caffeine and that is an herbicide. Herbicides hill plants, so the caffeine must be fully washed out to not harm the roots. Maybe if you got decaffeinated it would be ok, IDK, I toss them in the compost. Good luck!
SoOrbudgal
New member
Going2fast
New member
I compost all of mine. Do an experiment. Thoroughly flush enough to fill a planter, add lime and perlite, plant a seed and see what happens. Should be a good base providing the caffeine is gone.
dilvish
New member
yep I would do the same. essentially any inert organic compound could work. I just tried composted wheatgrass...results were mixed but seemed to do fine
I am not prepared right now to try a more ambitious test using the coffee as the primary media but I did have two OrangeVelvet clones ready to pot so I decided to try a safer test (I don't want to lose either plant). Both pots have a 4:1 mix of Whitney Farms Organic Potting Soil and Pearlite. The plant in the white pot has coffee grounds added (4:1:1 ratio WFO
earlite:Coffee). I also mixed in 1 tsp mycorrizal fungi to both. Will post more pics in a week or so. pH of runoff is 5.98 (wo) and 5.90 (w).
earlite:Coffee). I also mixed in 1 tsp mycorrizal fungi to both. Will post more pics in a week or so. pH of runoff is 5.98 (wo) and 5.90 (w).
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I just now flushed it with 2 gal. water (~5X the container volume). Initial runoff pH was 6.35 and it climbed to 6.8 by the end of the flush. Temperature is maintained between 60 and 75 in the box although I do see twice in the last week it spiked to 80 but only briefly. Humidity has varied between 30 and 60% over the same 7 days.
3Berries
New member
I had heard somewhere that caffeine will stunt the plant growth. I guess that's true.
But some interesting facts.
https://www.gardeningknowhow.com/ga...ilizers/will-caffeine-affect-plant-growth.htm
Will Caffeine Affect Plant Growth?
What purpose does caffeine serve, other than to keep us awake? In coffee plants, the caffeine building enzymes are members of N-methyltransferases, which are found in all plants and build a variety of compounds. In the case of caffeine, the N-methyltranferase gene mutated, creating a biological weapon. For instance, when coffee leaves drop, they contaminate the soil with caffeine, which curtails germination of other plants, lessening competition. Obviously, that means too much caffeine can have a detrimental effect on plant growth. Caffeine, a chemical stimulant, increases the biological processes in not only humans but plants as well. These processes include the ability to photosynthesize and absorb water and nutrients from the soil. It also decreases the pH levels in the soil. This increase in acidity can be toxic to some plants, although others, like blueberries, enjoy it.
Read more at Gardening Know How: Will Caffeine Affect Plant Growth – Tips On Fertilizing Plants With Caffeine
https://www.gardeningknowhow.com/gar...ant-growth.htm
But some interesting facts.
https://www.gardeningknowhow.com/ga...ilizers/will-caffeine-affect-plant-growth.htm
Will Caffeine Affect Plant Growth?
What purpose does caffeine serve, other than to keep us awake? In coffee plants, the caffeine building enzymes are members of N-methyltransferases, which are found in all plants and build a variety of compounds. In the case of caffeine, the N-methyltranferase gene mutated, creating a biological weapon. For instance, when coffee leaves drop, they contaminate the soil with caffeine, which curtails germination of other plants, lessening competition. Obviously, that means too much caffeine can have a detrimental effect on plant growth. Caffeine, a chemical stimulant, increases the biological processes in not only humans but plants as well. These processes include the ability to photosynthesize and absorb water and nutrients from the soil. It also decreases the pH levels in the soil. This increase in acidity can be toxic to some plants, although others, like blueberries, enjoy it.
Read more at Gardening Know How: Will Caffeine Affect Plant Growth – Tips On Fertilizing Plants With Caffeine
https://www.gardeningknowhow.com/gar...ant-growth.htm
SoOrbudgal
New member
That sucks guess it's another dang lesson, put some worm castings on it top feed, but I'd flush with Epsom salt first. Nice looking setup click
UndergroundFarmer
New member
Best bet is feed the used coffee grounds to the worms like we do in my house and months later you have some outstanding compost.
I had flushed several times but it still remained yellow. I also tried various nutes (calmag, azomite, epsom salt) and it did not respond to those either. Since that last post, I started feeding every other water with Fox Farms Grow Big and am finally starting to see improvement. Looks much greener now. Don't know what it was missing but FFGB seems to have it. Its the one in the middle along the back wall. I was waiting until I nursed it back to health before starting flower. Maybe soon...
