We all know that grinding your own coffee beans usually results in better tasting coffee, but what do you do with the used grind when you’re done with it? Do you throw it directly into the trash like most people? Do you save it for the garden like some avid composters and gardeners? Do you rinse it down the sink?
When I use my drip coffee maker, it’s super easy to pull the filter out of the machine and toss it all in the trash (or the compost if I’m feeling ambitious), but most of the time I make coffee from a French press or a moka pot. These are far more difficult to clean than just pulling out a filter and tossing it.
Can You Put Coffee Grounds Down the Drain?
The first couple times I cleaned my French press, I just rinsed it out in the sink and let all the grounds go down, but after doing some research on whether this was good for the disposal or not I found that it really can be a problem for your pipes. Not so much for the disposal, but the pipes further down the system.
This is important to remember if you brew only a cup at a time or use brewers like moka pots or French press pots where a paper filter is not present to hold all the spent grind. When you have to take grind out of the pot by hand, it’s important to get as much of it directly into the trash or compost pile or some other container for future use before you rinse the brewer out at the sink.
It’s inevitable that some grind will go down the drain. For instance, the little bit of grind at the bottom of your cup or the small bits that remain in a French press’ mesh screen that must be washed under flowing water, but if you use a lot of water and keep the grind to an absolute minimum then things should be ok for your pipes and your septic system.
Why Coffee Grounds Are Bad for Your Water Pipes
Coffee grind is basically a gritty substance or “mud” that can slowly start to form or exacerbate existing clogs. If you don’t rinse it away very slowly or run the water for a long period of time during the cleaning the grind can slowly build up in the pipes.
When the grind is still wet it is easily able to rinse away with plenty of water flow. Think about your coffee maker, though. Unused grind or freshly spent grind will wash away from your pot right away with little effort, but if wet grind is allowed to dry in the filter basket or on the bottom of your coffee pot you have to scrub it away.
In a pipe setting, the grind that is not adequately flushed away will settle in your pipes and harden, slowly forming a thick, cemented layer in the pipe. This will decrease the diameter of the pipe to the point where water flow is slowed and clogs eventually form. If you throw grease into the mix then the problem will become quite big, quite fast!
Coffee Grind is Bad For Septic Systems Too!
So you’re stubborn – just like everyone else. You decide it’ll probably be ok to slowly flush coffee grounds down the kitchen sink if you just do a little at a time and use a lot of water… but what about the septic system? Did you know that even if you were able to get all the grind to go through the pipes the coffee grounds would also put your septic system at risk for backing up?
In septic systems, coffee grind acts just like it does in pipes. It can get through the main septic chamber into the drain pipes. If the grind settles in the pipes, the overflow system can slow and cause a blockage, which can then cascade back through the system into your house.
As you can guess, if a lot of coffee grounds get into a septic tank then you will end up dealing with some hefty bills and headaches down the road. It’s just not worth it, especially when there are so many wonderful things you can use old coffee grounds for.
How to Keep Coffee Grind Out of the Drain
As we’ve discussed, coffee grounds in garbage disposal systems are a big no-no, so how then should you clean coffee grounds without putting them down the drain?
If you don’t want to reuse them, you can do what I’ve been doing for a while now. I’ve started rinsing the grind out into a paper towel which I’ve laid out to line the sink. I then either throw that away or drop the whole think into a compost pile, depending on how things are going in the garden. It makes things easier for me and it is safer for the pipes.
For my French press, I basically lay the paper towel over the drain and then put a bit of water in the pot and swish it around. I, then, slowly pour the water with all the spent grounds in it into the paper towel.
The towel holds the grind while the water passes through into the pipes. This keeps the vast majority of my mess away from my plumping and should prolong the healthy life of my pipes.
Things That Should Not Go Down The Sink Drain
Here is a short video that shows other things that you can’t or shouldn’t run through the disposal.
Where to Put Used Coffee Grounds For Later Use
OK, so you may not want to put your grind down the sink and you think you may want to start recycling it for other purposes later, but where do you put it?
It’s actually pretty simple to dry out old coffee grind if you lay it out flat on a paper towel, but one of the most common uses for used grind is in that garden. A popular solution to storing coffee ground for reuse is to get a countertop composter.
Just take your paper towel filled with grind and put it straight into the composter on the counter. The paper towel is just as compostable, so no worries there. Then, every few days or so empty the countertop jar into a larger compost bin outside or directly into a garden bed or lawn – after all the grind is healthy for lawns too!
Looking for something different to read?
I’d also like to invite you to take a look at this sweet page I put together on grinding coffee beans without a grinder. Keep it in mind the next time you go camping.
Don’t Put Coffee Grind Down the Garbage Disposal {Do This Instead}
Garbage disposals are simple kitchen appliances that make our lives easy as well as cut down the amount of food that goes into the garbage. Isn’t it so convenient to wash that food off of your dishes and not have to think about it ever again?
But if you use a reusable filter like a gold filter or a french press, you might wonder, if you can put those coffee grounds down the drain or garbage disposal.
The short answer is no.
Even though it looks like coffee grind will go down the drain it just won’t all go down and it won’t go down all the way. Slowly sediment will accumulate and you’ll have a big problem on your hands.
Is it Safe to Put Coffee Grounds in the Garbage Disposal?
It may seem harmless washing those grinds down, but years of buildup can make a big sludgy blockage as hard as concrete and as difficult to remove.
Coffee has sediment after all, so it is no wonder that it can cause further problems in your pipes. Even coffee shops know to keep the grounds out of the sink as best as possible to avoid costly repairs.
There are many articles singing the praises of coffee grounds as the best deodorizer for your disposal, even claiming they sharpen the blades. But in reality, old wet coffee doesn’t smell that great anyway and you risk clogging your plumbing. You will have better luck with a slice of lemon than with coffee grounds.
But instead of throwing them away, why not reuse them?
Here are some great ideas on how to reuse and repurpose what’s left of your old brew.
Use Coffee Grounds In the Garden Instead
Make Coffee Ground Compost
Composting is the most common way to reuse those grounds, especially when using a paper filter which will add carbon to your pile as a bonus. Just keep a small bin under your sink and when it’s full, take it out and throw it on your compost pile.
First, it will attract worms which are your friends when it comes to turning organic matter into soil. For some reason, they love coffee and we can’t blame them.
Second, it is going to add nitrogen. Coffee grounds have the same carbon to nitrogen ratio as animal manure. That is a double bonus, so you don’t have to buy smelly bags of the stuff and sling it around.
A composting study showed that coffee grounds that made up 25% of the compost pile caused the compost pile to stay hotter longer than animal manure which kills pathogens and weed seeds.
Coffee outperforms poop, awesome!
Use Coffee Grounds as Fertilizer to Boost Veggie Growth
Coffee can give that extra boost to root veggies like carrots and radishes if you plant the seeds with coffee grounds. Just mix the seeds with used, dry coffee grounds and sow them as usual.
Not only will the seeds germinate well, but you will get bigger, better carrots and radishes. It seems they like the caffeine too.
Coffee is a Natural Slug Deterrent
Sprinkle those used coffee grounds around the base of your plants and vegetables that slugs and snails love, and you will keep them away. It turns out that those coffee grounds have sharp edges like diatomaceous earth and it’s abrasive to them.
Now you can use coffee and your stale beer to get rid of slugs.
Blue Hydrangeas
If you grow these colorful bushes at home, you will know that different ph and nutrient factors affect the color of the blooms. Well, coffee supposedly turns them the most incredible blue hue.
Just walk out every morning after you brew your cup of joe and pour your coffee grounds right at the base of the plant.
Uses for Coffee Grounds in the Home
Use Coffee as a Fridge and Freezer Deodorizer
Like baking soda, coffee can be used in the same way, just put a small bowl of dry grounds in the back of your fridge and freezer. Simply replenish every few weeks. You will notice cleaner smelling appliances.
Use as a Natural Cleaner
For those who love to clean without chemicals like I do, coffee can be used to scour pots and pans like baking soda. In fact, you can mix it with baking soda for double the impact. The small amount of coffee grounds you will use to do this will not cause trouble for your plumbing.
Neutralize Odors on Your Hands
There is a reason why perfume counters have small bowls of coffee beans to cleanse your nose between smells. Coffee is a natural deodorizer and can remove odors from the air and hands. You can use old grounds with soap after you have cut garlic, onions or cooked fish to remove those pesky odors.
True story about coffee beans and odors. My husband bought a used square register off Craigslist for his business from a local cannabis store. Of course, the previous owner used to store some of his “goods” in the cash drawer. When we brought it home, we cleaned it with olive oil, but the cash drawer still smelled dank. I put a handful of beans and closed the drawer for a couple of weeks. And magically, the smell went away. I can’t tell you how amazing coffee is to neutralize odors.
You Can Even Grow Mushrooms with Coffee Grounds!
That’s right, if you love mushrooms, especially oyster or crimini, you can grow them at home using your very own coffee grounds. Just use a 5 gallon bucket with some holes drilled into the side and fill it half full with coffee grounds, then mix up some soil with it and put your mushroom spawn in. To find out how to do this click here.
Stain Paper
Give paper an antique or vintage look by dipping it in water mixed heavily with used coffee grounds. Dry on a line with clothespins, and you will have some beautiful hand dyed craft paper to work with.
Health and Beauty Ideas for Coffee
Try the Ever Popular Coffee Facial
Not for the faint of heart but it turns out that caffeine actually causes a tightening effect on the skin. Mix coffee grounds with some coconut oil and lather your face, especially under your eyes. You will see a reduction in bags under your eyes with this treatment.
Something to Brew About
We hope we gave you some new ideas to try to do with your old coffee grounds. It’s a shame to waste something so useful even after it has served its primary purpose.
If you find that you can’t get enough coffee grounds to use at home. Ask your local coffee shop. They would love to get rid of their extra grounds and you get to benefit from their surplus.
There are so many more uses for spent coffee; these are just some that we found most useful or interesting. We hope you found them helpful too.
Let us know what you do with your coffee!
