Coffee & Compost: The Truth About Coffee Grounds in the Worm Bin 

I'd Sell Both of my Children for coffee ☕😄

I gave up coffee a couple years ago but I drink a ton of loose leaf teas. The spent tea leaves are a staple in my Urban Worm Bags.

On the subject of acidity of spent coffee grounds, this does depend on the method used making the coffee. American brewing methods do indeed pass through a lot of water and hence relatively higher amount of acid is leached out of the coffee beans. Compare that with high end, high pressure, italian espresso machines which force through very small amounts of water through quite a large amount of coffee to give you only a 20ml shot of coffee. With this method the spent coffee is more acidic than the brewed method. I'm a former chemist and tested this both at home and at the lab where I used to work. I have the data if you're interested. Note I'm not saying that espresso grounds are too acidic for worms but simply that they are more acidic than you think and certainly not neutral.

I use coffegrounds as already composted material around my fruit trees and some heavy feeders like tomatos and pumpkins bc they are high in nitrogen and minerals.

I precompost my bedding and add the coffee and things like old fruit juice etc to the bedding with a couple handfuls of finished and finely sifted castings to get the microbes propagating in the bedding. It takes a week till the bedding is ready, but the worms seem to process it very quickly.

Try fermenting the grounds first with lactobacillus serum to make them into bokashi. Will make them readily available as a food source as well as cut down on any unpleasant smells. Great video brother.

Thank you. I have used coffee grounds in my worm bin for years. Everything you say conforms to my experience.

I have picked up 15,000 lbs. of coffee grounds from a local roaster/brewer a couple years ago and used them in my composting activity. I still have a large pile of straight coffee grounds and I have discovered that it is full of worms. Can these worms be used in a worm farm?

Thanks for explaining this.

Hi Steve, I just have a quick question; Do we have to sift the worm castings? Can't we just pick the worms out, put them back in the worm bin and put the gathered castings in the garden? By the way great videos

Love your Coffee and Compost segments! What is a commonly acceptable amount of coffee grounds one could add to an Urban Worm Bin in a week?

What about the caffeine? Will it keep my worms up at night?????!!!!!

I thought you would settle the score on the coffee topic that, I think, is very commonly disagreed on among vermicomposters. That is... whether or not coffee classifies as being grit. Over & over again I hear people refer to the coffee as being a form of grit - but if you ask me, it is not. What say you on this topic??...

Oh my God you made me spit my coffee out listening to the beginning of this video. Freaking hilarious and yes you are right I cannot do without my coffee.

this makes me more in love with worm farming and coffee

You made me laugh but also educated me. I agree about love of coffee. Thanks.

To paraphrase Robert Duvall in Apocalypse Now, I love the smell of coffee grounds in the morning. I've fed coffee grounds to my worms in moderation, and they seem to like it. However, great idea of letting the grounds fester for a while before feeding it to the worms. Makes sense, really, when you think of it! Great video as usual, Stephen, I find your videos very educational. The only thing I can't wrap my head around is that someone (one person as of this writing) would actually dislike this video. I mean, either a person is into worm farming, or they're not....but what is there to dislike? Lmao, it boggles my mind.

Do the coffee grounds have to be brewed?

Thank you, Steve! I will make my slimy babies coffee grounds/ banana peel/shredded cardboard stew tomorrow!

The worm will happier after get caffein intake 😂

I seriously love your content man from the Republic Of South Africa!!!

Thank you Steve, I should have asked you first before buying one, oh well, a new toy for the grandsons.

Steve - Thank You Urban Worm Company !!! I have learned so much. I have a worm bin so my grandkids can go fishing with worms without having to run to the store. Stop by for a Blue Gill Dinner!

That's the way I was doing it 60yrs ago. Always mix your grounds.

My first batch of worms was at a local ace hardware. They definitely were red wigglers. I put them in a closed 10 gallon tub with holes at the bottom ,top and sides near the top ,but below the lid line. I used coconut core and shredded paper for bedding. My reds did climb the walls the first night. The next day they settled in after giving them some blended greens that were liquefied by using a small blender. I received 250 reds Saturday and they seem perfectly happy. The first night the bin got a small blended salad. This morning I gave the bin a blended banana . I did add two coffee bags of Folgers grounds. I am feeding on one side only to build up castings on the one side for about 1 month. My aim is to have about 6 tubs and 6 thousand worms. I would like to sell some worms to pet enthusiasts. and fisherman in my town . Does this sound like a good plan to you? I am located about 30 minutes just southwest of Daytona Speedway.

Something else to consider - coffee grounds also still contain caffeine at lower doses but its there. This is actually a plant repellent - so other plants wont grow near it. In other words - compost it before adding to your garden.

I use the cold brew method and studies suggest that the caffeine level in the cold brew is higher. I don't know if that corresponds with the acid level but I imagine that most of the acid still winds up in the coffee itself. What I'm curious about is whether sprinkling the coffee grounds on top of the top layer of bedding (shredded paper) will help reduce the number of flies that inhabit your bin.

Used coffee grounds are acidic. The often cited study was flawed.

I can't abide coffee, and as an Englishment I drink tea. Lots of it. The worm seem to like the tea leaves.

What would be a good ratio of peat to coffee grounds for weekly feed?

I heard that coffee has a lot of chemicals from growers or processors in it that may be harmful. Is this true?

my worms don't look like that, they are small and kinda brown

Okay, quick question I bought two pounds of ANC's and used then to start a bin and my second UWB. I used a combination of coffee, spent grounds, and shredded paper. After 2 or 3 days, my worms effectively melted. I saved some from my UWB, but only a handful or two and I'm going to see if I can transfer then to a bin to try and repopulate. I also believe that flies, not BSF, laid eggs in the grain and those maggots may have harmed my worms. I have since thrown the rest of my spent grain in the compost to get it to start breaking down. Hopefully, I won't make that mistake again. My question is, what is the best setup to give my few remaining worms the best chance to repopulate. Any suggestions would be great.

Team Rubicon, I worked with them a few years ago when a tornado came thru our state, oh yeah I enjoyed the video also!

I'm new to composting, and now Im extremely curious about how my compost will be hence I drink coffee with mushroom and prebiotics.

Carbon to nitrogen ration 20/1 so 20 carbons to 1 nitrogen? That means carbon rich low nitrogen.

I almost never put fresh anything in with my worms. I often make a holding bin of stuff where it let it rot and maybe give it some water to get it composting before adding it to the worms. As he said it helps if you disinfected something or it was not really rotting at all to start with.

You’re teaching me so much, & yes I’ve been making many mistakes. I just bought 2 lb. African Night Crawlers from the most lovely Samantha @ Meme’s Worms to help my Wigglers here in SoCal. My wife and I are soon moving to the Oregon Coast. I will then order a truckload of garden non-compost worms for aeration and loveliness for the lawns and garden beds. Of course I’ll still have my composting worm bins as well as I plan on a large organic community vegetable garden on my property along with our personal garden.

thank you 🪱👍

👍👍This is awesome, exactly what I needed!

Good info.

Thank you for this excellent video!

tyvm i get the coffee growns from safeway from the starbucks there. there are alot in one bag. whats a good amount i should give. tyvm for the video was great to know about coffee. Free Internet Security

I add coffee grounds to the composter while still in the paper filter. I think that qualifies as a de facto green and brown composition.

thanks for you time to do the videos, and good advice

Quite logical actually; thanks.

Question: Is it possible to use manure (composted), cardboard, coffee grounds, worm castings to introduce the microbes and some worm chow and have a successful bin? This would NOT use any food scraps.

Very good. Can't think of a thing missed about coffee grounds you didn't cover. Agree 100% with everything said.

Vin Diesel is into worms?

I have a coffee roasting place nearby that will give away their chaff. This seems like it could be used as the dry brown material for bedding. Is there anything acidic about the chaff that would make these a bad material?

Legend mate great video. Thanks👍👍

Thank you 🙏

Cornmeal works about the same !

Thanks!

coffee grounds do not require composting. throw them right on top of the soil along with your crushed eggshells. I put my grounds into the potting mix I use for contaners both indoors and outdoors

Good looking out.

the sell your children thing was a little cringe

This is super helpful and thanks for sharing!!

Can I feed my worms lemongrass?

are flavored coffees ok?