Coffee grounds are chock-full of nitrogen, which helps speed decomposition by feeding the microorganisms that break down the biological material in the bin. Coffee grounds also contain other trace nutrients, including potassium and magnesium. Just pour in the grounds, mix, and walk away.

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Everyone knows that worms are great for the lawn and garden, but what you may not know is that worms are attracted to coffee grounds. The grounds are gritty, and worms need that grit to aid in their digestive process. And if you are using worms as fishing bait, mixing coffee grounds into the soil in the bait box will help keep the worms fresh and wriggling all day long.

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The same gritty texture that attracts worms to coffee grounds acts as a natural repellent to slugs, snails, ants, and other creepy-crawly bugs that can’t stand the acidity of coffee. Sprinkling coffee grounds on the soil around sensitive plants or mounding up a ring of coffee grounds a few inches out from the base of those plants will keep these pests away.

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Coffee grounds are acidic and therefore can be a great natural fertilizer for roses, azaleas, evergreens, rhododendrons, blueberry bushes, camellias, and hydrangeas. Adding coffee grounds to the soil around hydrangeas can produce vibrant blue blossoms, because the extra acidity helps the flowers absorb aluminum, leading to a deep blue hue.

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You may love the neighborhood kitties, but it's kind of gross when they use your garden as a litter box. Sprinkle some coffee grounds around your flower and vegetable garden beds to encourage cats to go somewhere else. You also can place coffee grounds around your indoor houseplants to deter kitty from snacking on the leaves.

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Before you clean out your fireplace, sprinkle the ashes with damp coffee grounds to minimize flyaway dust and debris. When cleaning the hearth at the end of the season, sprinkle a layer of dried coffee grounds along the back and sides and leave them there to eliminate any leftover smoke odors.

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Keep a small cup of coffee grounds near your sink, and use them to scrub your hands after you’ve worked with garlic, onions, fish, or other smelly items. The grounds will absorb the odor and also help exfoliate the skin.

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Use dried coffee grounds as a natural deodorizer for the refrigerator, freezer, closets, or car. Dry a batch of coffee grounds, and then place them in an open container to absorb odors in the fridge or freezer. For closets and cars, place dried grounds in a piece of cheesecloth or a section of old pantyhose; tie off the ends and then hang.

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Use coffee grounds to minimize scratches and scuffs on dark wood furniture. Start by placing some damp coffee grounds on the scratch, then work them in with a cotton swab. Let the grounds sit for 5 to 10 minutes, then buff with a clean soft cloth. You may need several applications, depending on the darkness of the finish. You can also rub coffee grounds on light wood furniture to create a weathered or antique appearance.

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The tannins in coffee grounds make them effective for dyeing Easter eggs, fabric, or paper. Mix grounds with a little bit of water to create a slurry, and then dip the objects to be dyed into the mix. The longer you leave an item in the mixture, the darker the shade of brown you'll obtain. To create a streaky, antiqued look, rub the grounds into the fabric or paper.

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Salt is a commonly used de-icing product for winter walkways and driveways, but it can also damage sensitive plants and over time can even wear away cement or asphalt surfaces. Coffee grounds are a great alternative for making sidewalks and driveways less slippery; the acid in the grounds also helps melt the ice.

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