potpimp
Sector 5 Moderator
I've been on here long enough to hear it all... "I piss on my plants", "my cat pisses on my plants", etc. Most of it - and most of what you read on this forum - is BS, tales passed from one noob to the next. Uncle Ben refers to these as "snake oil and rocket fuel". However, I recently read on a forum for master gardeners about using cold coffee on tomatoes. There was no science given but it sounded reasonable so I tried it on my tomatoes... and on a couple of my pot plants. While it is impossible to quantify the results, it does appear that it may have had some beneficial results. I used the cold coffee several times over the course of a week.
Now for the good part. I decided to check the pH of the residual of yesterdays coffee. But I needed a standard to go by so I checked my tap water first: 7.5. Then I poured the cold coffee into a glass and tested it: 5.5! That was interesting, a perfectly pH balanced amendment for our favorite plant.
I Googled for information on what is in coffee. There are over 1,000 chemicals in coffee but only a few of them in a significant proportion. I will list the major ones.
Water - the universal super solvent.
2-Ethylphenol - a component of cockroach alarm pheromones.
3,5Dicaffieoylquinic acid - a powerful antioxidant that destroys free radicals.
Dimethyl disulfide - you don't want to know.
Acetylmethylcarbinol - gives butter it's buttery taste; it's also used in movie popcorn flavoring.
Putrescine - you really don't want to know!
Trigonelline - a niacin molecule with a methyl group attached. It prevents tooth decay by inhibiting the bacterium streptococcus mutans from attaching to your teeth.
Niacin - Vitamin B3. When coffee is brewed, the high temperature causes the methyl group to detach from the niacin, releasing pure niacin into the coffee.
Coffee grounds also seem to be a very good material to add to your compost pile and even freshly used grounds are fine to use.
OK, I'm not a scientist but I did stay at a Holiday Inn Express last night. So my conclusion: use it; it can't hurt and there seems to be some good things in it. ...but I wouldn't use it in my hydro unit.
Now for the good part. I decided to check the pH of the residual of yesterdays coffee. But I needed a standard to go by so I checked my tap water first: 7.5. Then I poured the cold coffee into a glass and tested it: 5.5! That was interesting, a perfectly pH balanced amendment for our favorite plant.
I Googled for information on what is in coffee. There are over 1,000 chemicals in coffee but only a few of them in a significant proportion. I will list the major ones.
Water - the universal super solvent.
2-Ethylphenol - a component of cockroach alarm pheromones.
3,5Dicaffieoylquinic acid - a powerful antioxidant that destroys free radicals.
Dimethyl disulfide - you don't want to know.
Acetylmethylcarbinol - gives butter it's buttery taste; it's also used in movie popcorn flavoring.
Putrescine - you really don't want to know!
Trigonelline - a niacin molecule with a methyl group attached. It prevents tooth decay by inhibiting the bacterium streptococcus mutans from attaching to your teeth.
Niacin - Vitamin B3. When coffee is brewed, the high temperature causes the methyl group to detach from the niacin, releasing pure niacin into the coffee.
Coffee grounds also seem to be a very good material to add to your compost pile and even freshly used grounds are fine to use.
OK, I'm not a scientist but I did stay at a Holiday Inn Express last night. So my conclusion: use it; it can't hurt and there seems to be some good things in it. ...but I wouldn't use it in my hydro unit.
