How to Compost Coffee Grounds

If your summer garden isn’t doing as well as you hoped, making compost with used Dunkin'® coffee grounds may help your plants flourish. And if you’re already composting, coffee grounds can supplement your garden with magnesium, phosphorus and other nutrients.

Compost is a nutrient-rich soil additive made from decomposed organic material such as food scraps, yard waste, leaves, and other natural materials. It is created through a natural process called composting, in which microorganisms break down the organic materials over time into a dark, crumbly substance. Composting can be used to improve soil health and fertility in gardens, farms and landscaping, and is a sustainable and eco-friendly way to recycle organic waste and reduce landfill waste.

Compostable materials are divided into two categories: brown and green materials. The difference between brown and green materials lies in their carbon-to-nitrogen ratios. Brown materials are dry, carbon-rich materials that provide structure to the compost pile. This includes materials like twigs, shredded paper, dry leaves and even coffee filters. Green materials, on the other hand, are moist, nitrogen-rich materials that provide the nutrients needed to break down the brown materials. Examples of green materials include grass clippings and vegetable and fruit scraps. 

Coffee grounds are a popular addition to composting material, and they can have several beneficial effects when added to compost piles.

• Coffee grounds considered green materials, as they are rich in nitrogen, an essential nutrient for plant growth. When added to compost, coffee grounds can increase the nitrogen content, helping to balance the carbon-to-nitrogen ratio that is necessary for effective decomposition.
• Coffee grounds can improve the structure of compost by helping to aerate the mixture and improve drainage. This can be especially useful for compost piles that are prone to becoming compacted and waterlogged.
• Coffee grounds can attract beneficial microorganisms, such as bacteria and fungi, which help to break down organic matter and create rich, nutrient-dense compost.

It's important to note that while coffee grounds can be a valuable addition to composting material, they should be used in moderation. Excessive amounts of coffee grounds can increase the acidity of the compost, potentially harming beneficial microbes and reducing the overall effectiveness of the composting process.

Ready to learn how to compost with coffee grounds? We have you covered. 

1. Pick the Location 

Decide where you want to start your compost pile or bin, whether that’s indoors or outdoors. Ideally, it should be in a spot that is easily accessible, but also out of the way. Outdoor composting requires a sunny and flat location, plus a good drainage spot. Keep in mind composting can create an odor, so it’s best to keep it away from heavy traffic areas.

2. Choose a Compost Bin

Indoor composting bins vary in size and technology, so choose one that works for you. Outdoor composting can use a bin, coffee canister, or simply be done in a pile on the ground. It should be large enough to hold materials, but small enough to stay out of the way.

3. Gather Materials

In order to create a healthy, balanced compost pile, it’s important to have a mix of both brown and green materials. Generally, a good rule of thumb is to aim for a ratio of about 2-parts brown materials to 1-part green materials. This will help ensure that the pile stays moist, aerated, and active throughout the composting process, ultimately resulting in the nutrient-rich compost you’re looking for.

4. Layer Brown and Green Materials

The first layer of your bin or pile should include brown materials. Twigs and sticks are a good base, followed by dried leaves and other carbon rich material. After the brown base, green materials should follow. All materials should still be moist, which makes used coffee grounds from your at-home coffee perfect for the job. 

5. Continue to Layer

After the brown and green layers are set, collect kitchen and yard waste to add to your compost bin. Add these items in separate layers and continue to do so until the bin is full.

6. Maintain and Monitor

Whenever you add new material, blend the top layer with the other layers by spinning the bin or mixing with a shovel. This will help mix the materials and provide air to the pile, which is important for the composting process. Check the temperature of the compost pile regularly. If it gets too hot, add more brown materials. If it’s too cold, add more green materials.

7. Harvest the Soil

Most DIY compost takes four to six months to be ready. Finished compost will be dark, crumbly, and smell like the earth. If materials are still in the process of breaking down, leave those in the pile or bin. Those materials will help new layers turn into compost.

With these simple steps, and leftover Dunkin’ coffee grounds, you’ll be on your way to creating nutrient-rich compost for your garden and reducing waste at the same time. If you prefer using Dunkin’ K-Cup^® pods, you can still get in on the composting! Simply open up used K-Cup^® pods and scrape the grounds into your compost pile. Who knew your cup of coffee was good our garden?! Happy growing.

If you’re looking for new ways to use coffee grounds beyond your daily cup, check out our new coffee recipes​. 

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