Are Used Coffee Grounds Good For Plants? Read This First!

Others recommend recycling used coffee grounds and add them as a fertilizer for gardening. But are used coffee grounds good for plants? Read to learn more.

used coffee grounds added as fertilizer to a potted plant - Are Used Coffee Grounds Good For Plants
Used coffee grounds is good for your garden

You know you love your morning coffee — but did you know that the grounds left behind can be used for the good of your fruit and vegetable garden? Coffee grounds slightly increase the acidity of the soil, which is a recipe for growth for many types of plants. 

You can also add coffee grounds to your compost pile. Composting with coffee grounds can increase the nitrogen in your compost pile, which can help sustain higher temperatures over time. 

Here, we'll explore everything you need to know both about using coffee grounds to support plant growth and using coffee grounds to break down organic materials (like food scraps, veggies, dried leaves, grass clippings, and other green compost items beloved by earthworms) in your compost pile. 

Coffee Grounds For Plant Growth

Different plants thrive in different types of soil. Acid-loving plants can benefit greatly from coffee grounds being added to soil, or used under mulch around the base of the plant's stem. Alkaline-loving plants, on the other hand, won't likely react as well to used coffee grounds as fertilizer. 

Acid-Loving Plants Vs. Alkaline-Loving Plants

newly sprout plants in a garden plot
Know more about your plants first

To know how to serve your garden best, you first need to differentiate between which of your plants love acidic soil, and which plants thrive in a more alkaline environment. 

Daffodils, blueberries, azaleas, rhododendrons, camellias, hydrangeas, and mountain heather all tend to do well in an acidic environment. Many trees also tend to prefer acidic soil, including magnolias, beech, oak, willow, dogwood, and mountain ash. 

Plants that tend to thrive in a more alkaline environment include cherry blossoms, lilacs, forsythia, clematis, and bluebeard. While these plants may still grow in soil treated with coffee grounds, they're likely to live longer and grow stronger when provided with alkaline soil. 

Steps To Using Coffee Grounds In Your Garden

Using Coffee as Compost
Follow this steps in applying coffee grounds as a fertilizer

Applying used coffee grounds to your garden as fertilizer for your plants is a simple process:

  •  After you're done making coffee in the morning, allow the coffee grounds to cool to room temperature. 
  • Sprinkle them in a light layer at the base of your acid-loving plants. 
  • You can work them into the top layer of the soil using your hands, or using a small garden trowel. 
  • Then, you can cover the coffee grounds with a light layer of mulch to ensure that they stay moist. If coffee grounds dry out, they can repel water, so they must be covered with organic material.
  • Remember, it's ok to troubleshoot, whether you're using coffee grounds as a pesticide or solely as fertilizer. Trying coffee on different types of plants, changing up the caffeine content by using decaffeinated coffee grounds, or switching up the number of coffee grounds you use in the soil can all make a difference. 

In addition to creating a more acidic environment for your acid-loving plants to thrive, adding coffee grounds to the soil also: 

  • Improves the soil structure, helping the roots to take a keep a stronghold in the ground
  • Works as a repellent for many pests, including slugs and snails
  • May inhibit the growth of weeds around the plant's base

Coffee Grounds For Compost

green garden fork in a compost pile
Coffee grounds helps break down organic plants and other materials in your compost pile

You can also use coffee grounds to help break down organic plants and other materials in your compost pile. This isn't just good for the environment — it's convenient for you as well. 

Be sure to check the label of the coffee filters you're currently using to find out whether you can simply toss them into your compost pile as well. Many coffee filters today are compostable, and work well as a carbon source for your compost pile.

It's important to add a carbon source (you can use dry leaves if you don't have compostable coffee filters) when you add used coffee grounds to your compost pile. 

To successfully add coffee grounds to your compost pile: 

  • Layer leaves, grass clippings, and coffee grounds (in that order), and turn weekly. 
  • You can also simply add coffee grounds to the compost pile you already have in your yard. 
  • Going through coffee grounds faster than you can compost them, or want to save them for a future compost pile? Store them in a large plastic bag. If the grounds develop mold, no worries — it will be decomposed during the composting process.

The Final Word On Are Used Coffee Grounds Good For Plants

Going green by using coffee grounds in your garden is a smart move. You can add coffee grounds to the soil surrounding acid-loving plants, or add ground-used coffee to your compost pile. If you're overloaded with coffee grounds, set them aside in a plastic bag to add to your compost pile at a later time. 

FAQs on Are Used Coffee Grounds Good For Plants

Do all plants benefit from adding used coffee grounds to the soil?

Not all plants — only those that thrive in acidic soil. Daffodils, blueberries, azaleas, rhododendrons, camellias, hydrangeas, and mountain heather are just a few examples of acid-loving plants. 
 

How do you add coffee grounds to a compost pile?

If the compost pile is new, add one layer of leaves, one layer of grass clippings, and one layer of coffee grounds (repeat). If the compost pile already exists, simply add the coffee grounds on top.

Be sure to mix in a carbon source, like torn-up paper coffee filters or dry leaves, to balance out the nitrogen content added by the ground coffee.
 

I don't make my own coffee. How can I get used coffee grounds?

Many coffee shops are happy to provide customers with spent coffee grounds for gardening and composting. Next time you grab a cup of coffee, ask your favorite barista if they'd be willing to donate to your cause.
 

Author

  • Amanda Turner is a runner, writer, mom, and military spouse living in San Angelo, Texas. A former track coach, Amanda loves encouraging and working with new runners who are just beginning to love the endorphin rush that hits a few strides after the finish line. When she's not running or writing, Amanda, her husband, and their three-year-old love traveling and spending time outdoors.