5 ways your coffee addiction can boost your garden

Coffee isn't just great at perking you up in the morning. It's great around the garden, too.

Taylor Martin CNET Contributor
Taylor Martin has covered technology online for over six years. He has reviewed smartphones for Pocketnow and Android Authority and loves building stuff on his YouTube channel, MOD. He has a dangerous obsession with coffee and is afraid of free time.
Taylor Martin
3 min read
Taylor Martin / CNET

If one of the first things you do each morning is brew a fresh pot of coffee, then you likely have a lot of coffee waste. After the brewing is finished, you grab the filter and dump the grounds in the trash. But did you know you can use those spent grounds around the house instead?

You can use coffee grounds to make coffee-scented candles, as a body scrub and even to clean stubborn food residue off pots and pans. But they're particularly useful outdoors. From pest control to worm food, here are five ways coffee grounds can help your garden grow.

Read more: Check out CNET's guide to growing a healthy garden and keeping it that way.

Compost boost

Rather than tossing out your spent grounds every morning, save them and add them to your compost pile. Coffee makes a great natural fertilizer when composted. It can increase nitrogen, phosphorus, potassium, magnesium and copper levels in the soil.

Don't get too crazy, though. Adding too much coffee to the compost pile can raise the acidity, negating many of the benefits. Try to keep the grounds to roughly 25 percent of the pile or less.

Best of all, you don't even have to separate the grounds from the filter. Paper coffee filters are biodegradable and can go straight into the compost, too.

Lower pH levels

Of course, some plants like that extra acidity. Azaleas, gardenias, carrots, strawberries and many other plants thrive in acidic soil. For these plants, you can add a small amount of grounds to the soil while planting. The coffee can help the germination process and promote healthy growth.

Altering the pH level of the soil can also change the flower color in plants like hydrangeas.

Watch this: 5 tips and tricks for brewing better coffee at home

Pest deterrent

Sprinkle a barrier of coffee grounds around your flower bed or garden to help keep unwanted pests out. Caffeine is a natural pesticide that can paralyze or kill many insects. It will help keep destructive slugs and snails at bay. But it can also help control mosquitoes, bees, wasps and you can even sprinkle it around ant hills.

Attract worms

Worms love to eat coffee grounds, and that's great news for your garden. Add coffee grounds to your compost pile to help attract worms, which help speed up the process of turning food scraps into compost.

You can also add coffee grounds directly to the soil, but you'll have to be careful not to overdo it. Sprinkle a light coating of coffee over the top of the soil or till a light mixture into the soil. This will help draw in earthworms, which increase the amount of air and water in the soil.

Flower pot liner

Your coffee filters can be put to good use too -- and not just in the compost pile. You can line the inside of flower pots with a coffee filter to prevent soil from escaping the bottom of the pot when you water the plant. Because filters are permeable, they'll still let water drain out.

Learn everything you need to create a beautiful, healthy garden with CNET's gardening guide.

How does your smart garden grow? We test the latest gardening tech.