5 Easy Ways to Re-Purpose Your Coffee GroundsPublished on 07/07/2022 · 7 min readCoffee & Espresso Expert Hannah Ramsey gives 5 genius ways to get a bit more life out of those leftover coffee grounds, plus a few bonus ideas!
Photo by Tyler Nix
No matter the brewing method—whether you’re tamping an espresso, hand pouring a drip coffee, brewing in a French press, or steeping grounds overnight for a cold brew in the morning—nothing is better than freshly ground coffee.
But what are you going to do with the coffee grounds? Should you just throw them out as garbage? Can you use the old grounds to rebrew another pot of coffee? Is there any way to repurpose those beautiful grounds? The answer is a resounding yes.
There are several ways to reuse coffee grounds. But sadly, re-brewing isn’t one of them. Once an initial extraction has been done, most of the caffeine, rich flavors, and aromas have been removed. However, if you’re interested in putting your old grounds to work for you, here are five foolproof and handy ideas.
1. Fertilize House Plants and Gardens
Because coffee contains trace minerals important for growth, including nitrogen, potassium, phosphorus, chromium, magnesium, copper, manganese, zinc, and iron, it can be used as a fertilizer for certain plants. It’s also a great organic matter that attracts decomposers like worms and aids microorganisms that live in your soil by adding to the bacterial growth that helps in nitrogen absorption.
Used coffee beans have a neutral Ph level of about 6.5 - 6.8 that doesn’t affect soil acidity, so plants that enjoy acidic soils won’t be affected negatively. Using freshly ground coffee beans increases soil Ph, which is perfect for acid-loving plants like veggies such as garlic and onions, herbs such as rosemary and thyme, and flowers like azaleas and rhododendrons.
Farmers tend to use coffee grounds over other organic materials because of their density. Similar to mulch, coffee grounds act as a ground cover and protect soil from too much moisture. Grounds won’t blow away like lighter substances such as Perlite which is a commonly used fertilizer made by processing lava rocks.
When using grounds, it’s important to note that freshly ground coffee beans will still contain some amount of caffeine and acidity harmful to plants like tomatoes, orchids, and lavender. They aren’t healthy for just any plant, so do your research ahead of time!
Homesteaders, farmers, and gardeners add used coffee grounds to their compost bin. The nitrogen and fungal properties of coffee have enzymes that aid the growth of mold and good bacteria and speed up decomposition, creating nutrient-dense soil.
It’s easy to add used coffee grounds to any compost pile by layering the ingredients using leaves, fresh grass clippings, and coffee grounds in equal ⅓ parts. If you use paper filters to brew your coffee, it’s even easier to throw in the used grounds as you don’t have to remove them from the filter. Just tear it up into smaller pieces to give a boost to the decomposition process!
It is also important to note that, because coffee is an organic substance and it contains bacteria-friendly enzymes, if you keep damp grounds in a closed dark container, they will become moldy. Make sure that if you store your grounds indoors, later put them into a compost pile in a cool, dry, open, and airy environment to prevent mold growth.
3. Impede Pests
One of the biggest attractors of bugs and pests is a garden full of unhealthy plants. Using coffee as a fertilizer in soil for potted plants, container gardens, or crops grown in tilled land deters pests that feed off of weakened environments.
Snails and slugs are big killers of vegetable crops such as lettuce and cucumbers. Fortunately for a coffee lover, neither of these slimy creatures are fans of the brown stuff and avoid it at all costs. Ants are another nuisance that can’t handle coffee’s aroma or acidity. Placing grounds on top of an anthill or adding a layer around your home’s foundation stops the bothersome insects from invading your domain.
If you’re a pet lover, you may know most cats dislike coffee. Coffee grounds are a great way to prevent your cats from snacking on some of your plants. Dogs, however, may be attracted to the scent. Monitor them if using grounds in your garden as they shouldn’t consume caffeine.
If your pets have had fleas, you know how hard it is to remove these bugs at the root level. Luckily, you can rid yourself and your poor little fur baby of the infestation by bathing them in with a mixture of equal parts water and coffee grounds; genius.
4. Natural Cleaner
There are many ways to clean different parts of your house with used coffee grounds, but here are a few simple suggestions.
If you have stinky shoes or a weird smell in your fridge that won’t go away, even with baking soda, grounds absorb and block odors. Simply dry some out in a mason jar on your closet shelf or in the back of the refrigerator. Use an old sock or stockings to make a coffee ground ball to stuff in your work boots or tennis shoes to catch any odors before they escape.
There are many benefits to using your grounds to make shampoos and body and face scrubs for multiple skin types and issues. Coffee’s nutrients and exfoliating properties invigorate skin and remove dead cells.
Additionally, if you handle garlic or onions in the kitchen, scrub your hands with some grounds and coconut oil to rid them of the smell immediately and soften your skin at the same time.
5. Add to Recipes
Is there a recipe you make weekly that needs a bit of spicing up? Coffee is an excellent ingredient to add for a taste update. Use some as a dry rub for smoking and grilling meats, or bake them into granola or pastries like cake and cookies.
Coffee is known as a metabolism booster and a rich source of B2 vitamins and magnesium. Consuming coffee in many forms has additional health benefits that fight against several chronic diseases.
Incorporating used grounds into a recipe won’t give it the same intensity as fresh coffee grounds. However, if you substitute used grounds in place of the fresh, you add flavor while avoiding additional caffeine that would be extracted and absorbed by your dish while cooking.
Bonus Coffee Ground Uses
- Keep a container of grounds by the kitchen sink and use them to scour any dishes or pans with tough, baked-on stains. It’s a fantastic way to scrub cast iron without stripping the pan of any seasoning.
- Cleaning a fireplace is the bane of its routine upkeep. Place wet grounds over the ash and soot to make it easier to clean. This keeps them from going airborne when sweeping up your hearth and you won’t have to cover every piece of furniture you own.
- As roaches are attracted to the aroma, use coffee grinds to lure cockroaches to a trap.
- If you have spilled coffee on your clothes, you know there’s next to nothing that removes the stain from the material. Turn it into a happy accident by brewing up some grounds in a large pot and using it as a natural dye. Turn those not-so-whites into an off-white on purpose! Or use it as an alternative to henna to give your hair a brown or copper tint. The caffeine rejuvenates your scalp and adds shine to your locks, too.
- For art projects, try grinds instead of glitter on glue to make shapes and writing. Or use them to add an antique effect to notes or scrapbooks.
So, whether you drink just one cup of coffee a day or several, sip happily, knowing there are many eco-friendly uses for the grounds left behind after brewing.
If you're left wondering about the perfect brewing method, chat with a Coffee & Espresso Expert about their favorite machines.