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Using Coffee Grounds for Gardening (Plus 5 Additional Fertilizers)

Reginald is a retired educator with a passion for gardening. For the past 30 years, he has proven techniques and loves sharing with others.

Coffee grounds

Coffee grounds

Are you part of the over 150 million people in the United States that drink coffee? Most of us have a cup or two at home before going to work. If you are like me, you might have a cup when you get home.

So now that we have established that we all drink coffee, what's my point? It's simple! What do you do with the coffee grounds? Well, most people dispose of them in the trash. That's ok, but did you know that coffee grounds are a great fertilizer for your garden?

Read on to the end and learn about using coffee grounds for gardening, plus five additional fertilizers. By the end of this article, you will want to save your coffee grounds and become a better gardener.

Let's get started!

Organic vs. Synthetic Fertilizers

There have been many debates over which is more beneficial to a garden—organic or synthetic fertilizers. This gardener is very much in favor of using organic fertilizers for a few reasons.

Many are items that we have around the house, including coffee grounds. Organic fertilizers work with and enrich the soil of your garden. The soil, in turn, feeds your plants.

Synthetic fertilizers are man-made chemicals that give your plants a quick hit of energy. The chemicals will soon wash away, leaving your plants wanting more. This means that they don’t have anything to do with the soil. You will end up having to use more synthetic fertilizer for the plant.

Nutrients Contained in Coffee Grounds

Coffee grounds make for a great fertilizer in your garden because of the nutrients they contain. The “Big 3” primary nutrients are nitrogen, phosphorus, and potassium. Let’s break these three nutrients down for an inside look at them.

  • Nitrogen (N) - Nitrogen helps strengthen the roots and leaves of plants. This is one of the reasons why coffee grounds are used in gardening. Coffee grounds contain approximately 2% nitrogen, a necessary part of chlorophyll that makes the leaves green and helps plants photosynthesize.
  • Phosphorus (P) - The second of the Big 3, phosphorus, is linked to a plant’s ability to use and store energy, including the process of photosynthesis. It’s also needed to help plants grow and develop normally. We need phosphorus for developing flowers, fruits, and root systems. Coffee grounds provide 0.06% phosphorus.
  • Potassium (K) - Potassium is the third key nutrient of commercial fertilizers. It helps strengthen plants’ ability to resist disease and plays an important role in increasing crop yields and overall quality. Roots are kept healthy and help produce flowers and fruits. Potassium helps plants tolerate stress, such as drought. Coffee grounds provide 0.6% potassium for your soil.

How to Prepare Your Coffee Grounds

If you grind your own coffee beans, don't do anything special. Remember, we are going to save the grounds for later use. Pre-ground coffee comes in a bag or the "coffee can." These are easy to work with as you just need to find a container to store the grounds in. A great receptacle is an old coffee can with a cover. If you want your coffee grounds to be useful as fertilizers, then use the grounds that are dried out completely. The nutrients will get stored inside them since they are not so sticky, making them better for the plants.

Coffee Grounds Tea

I was out in my garden one day, and my wife had just finished making a large container of sun tea. Yummy! Drinking the tea gave me an idea. Many of us are using the new Keurig-type coffee machine these days. The ones that brew your coffee through a small pod. One of the more interesting techniques that I use now to fertilize my garden plants is what I call "coffee grounds tea."

  1. Take 10 used pods and put them in a large plastic sealable bag. Before closing it up, fill the bag with water.
  2. Bring the bag down to your garden area and leave it in the sun for a day.
  3. The next morning, take a pair of scissors and cut one of the corners off.
  4. Carefully pour the "tea" around the plants you want to fertilize. Try to make your circle around the plant about 6 inches away from the stock. This will get better distribution to the roots.

Now I am not telling you that I invented this technique, but it is interesting what the mind will come up with if you just sit, relax, and think.

A variation on this theme would be to take a five-gallon bucket with a cover, put two cups of coffee grounds in and fill it with water. Cover the bucket and let it sit for a day—instant coffee grounds tea for your plants. You can use this method of coffee grounds tea once every week.

5 Additional Fertilizers to Use With Coffee Grounds

Now that I've gone over using coffee grounds as fertilizer, I'd like to discuss five other fertilizers you can use in gardening. Understanding the treasure of coffee grounds will help you appreciate these next five. Don't forget the magic word—"organic."

  1. Compost
  2. Eggshells
  3. Bone Meal
  4. Fish Emulsion
  5. Chicken Manure

1. Compost

Compost is one of the best organic materials for your garden. It is a natural process that turns organic matter like food scraps and yard debris into rich dark material. Compost is an incredible soil builder. Some people say that compost is not a fertilizer. I say that without compost, your garden will suffer. This material is the best fertilizer to build your soil.

Compost feeds your soil. In turn, the soil takes care of the plants, offering a smorgasbord of nutrients, pest and disease resistance, and more. But those nutrients are slow-release, feeding plants over time. And that is a good thing. The benefits of a single compost application can stretch over multiple seasons.

Compost’s nitrogen, phosphorus, and/or potassium values are low compared to synthetic fertilizer. This means that building your soil depends on you providing plenty of compost.

That said, compost’s NPK value does have a dollar value. The nutrients delivered by a compost product should be a factor in any input decisions involving synthetic fertilizer purchases. Compost will add a slew of micronutrients not typically found in common synthetics and improve nutrient uptake.

I make it a daily practice to build my compost. My compost tumbler is the same one below. It works like a charm. I feed and turn it every day, and it gives me nice dark rich compost in a very short time.





2. Eggshells

Eggshells are a great fertilizer for your vegetable garden. You can take used eggshells, put them in your blender, and grind them into a fine powder. Doing this process for a number of weeks will provide you with an ample amount of eggshell fertilizer.

There are various uses for powdered eggshells. One is to add a few teaspoons of this powder into the hole before planting a new veggie. It is possible to use whole eggshells in your soil, but they will decompose much faster if they are crushed or ground into powder.

Another method would be to add crushed or powdered eggshells around the base of a plant. You don’t need to cover the eggshells with soil. As they decompose, they will leech calcium and other nutrients into the soil. This helps your plants to grow strong and healthy.

Compost Them

Composting is a great method of building your garden soil. Except for meat, collect table scraps, including egg shells, and add them to your compost area or bin. Keep doing this on a regular basis, and you will be rewarded with the best organic fertilizer for your soil.

3. Bone Meal

Another organic fertilizer for your garden is bone meal. This type of fertilizer is made by grinding animal bones into powder. The powder contains phosphorus and nitrogen to help the plants produce new leaves and roots. Use bone meal each and every season. This is a great one-two punch of organic material.

4. Fish Emulsion

Fish emulsion is another excellent organic material that you should have handy for fertilizing your garden. I use this on a regular basis when fertilizing my plants. If you are one that prefers to keep away from synthetic chemical fertilizers—this is the ticket. It comes in a bottle and is very concentrated. A bottle of this fertilizer will last many seasons.

5. Chicken Manure

Chicken manure is another organic fertilizer that adds to the success of gardening. It contains those three primary nutrients—nitrogen, potassium, and phosphorus.
Although composted cow manure is an excellent additive to your soil, I use chicken manure mixed with coffee grounds to sprinkle around a vegetable plant. A little bit will go a long way. Try it! You will love the results.

Additional Facts About Coffee Grounds

  • Coffee grounds attract earthworms. Earthworms are fantastic for your garden.
  • Grounds from coffee are very good for repelling bugs and insects that may bother your plants.
  • To use coffee grounds as an insect or pest repellent, simply place bowls of coffee grounds around the garden or seating area.
  • Coffee grounds are great for deterring mosquitoes, fruit flies, beetles, slugs, and snails.
  • Sprinkle these grounds around your house plants and watch them grow.
  • The coffee grounds fertilizer can help you grow more vegetables and fruits, but you also have to pay attention to their use in your garden. Thus, the main reason people prefer using coffee grounds for gardening is the convenience and cost-effectiveness of doing so. You can be sure that the process will take only a few minutes, and you can get great results.

Use Coffee Grounds for Amazing Soil

If you are new to gardening and serious about it, your goal should be to develop the best soil. Your garden soil takes years to cultivate. Using coffee grounds for gardening is one technique that is easy to do and very beneficial to your soil.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2022 Reginald Thomas