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Are Coffee Grounds Good For Growing Basil? Everything You Need to Know

Coffee grounds and basil growing indoors

So you’re growing your own basil and want to know if you can use spent coffee grounds as fertilizer.

Short answer: Yep, using coffee grounds to aid basil growth is a great idea!!  Read to learn why.

I used spent coffee grounds and tea bags for some extra zip when I grew African violets. You’ll be pleasantly surprised at the results.

Before you do, though, it’s a good idea to know what’s in coffee beans that benefit our plants. Is it different after the coffee has been brewed? What does it do to the soil or even to the basil plant? All this and more we’ll discuss so you’ll know how to grow the best quality basil around.

adding fertilizer to garden

A Word About Fertilizers

Fertilizers aid in plant growth with hearty fruits, beautiful flowers, and strong roots. They add nutrients to the soil that the very plants they protect took out of it. Fertilizers come in synthetic and organic. Organic fertilizers consist of plant and animal components (think manure for animal and wood chips for organic.)

The big three of the fertilizer world are nitrogen, potassium, and phosphorus. These nutrients are vital to the development of the plant. Nitrogen is vital to the production of protein, and protein comprises the majority of the tissues in most everything, including us.

Phosphorus gives a plant the ability to store and use energy such as photosynthesis. It helps a plant grow normally. Potassium is the third key to healthy plant life. It’s necessary for the plant to resist disease and produce quality food. It strengthens the root system and protects the plant from cold and drought.

Plants need the same vitamins, minerals, and amino acids that we do, although for different reasons. Magnesium, manganese, calcium, folate, choline, sodium, and much, much more give plants the ability to go through photosynthesis as well as to enjoy a healthy diet. 

Adding coffee grounds to plants

Where Coffee Grounds Enter The Picture

Working spent coffee grounds into the soil around your plants or before you plant introduces organic material into the soil. This aids in soil aeration, water retention, and better drainage. The spent coffee grounds also support the microorganisms that help the plants grow. Earthworms love coffee, too.

If you’re worried about the acid level of the soil, don’t be. Dry coffee grounds are highly acidic, but you’ll be using spent coffee grounds. That’s a horse of a different color because spent coffee grounds have a pH level of about 5.5 to 6.5 in the neutral ballpark. Growing basil requires a pH level between 5.5 and 6.5.

Note: Keep the grounds thinly spread. If you don’t, they’ll clump up and prevent water from getting to the roots of your basil plants.

The Difference Between Fertilizer, Compost, and Mulch

We’re talking about fertilizing basil in this article, but some gardeners might be confused when they read about compost or mulch. Let’s take a minute to discuss what these things are, their potential for plants, and if they differ from fertilizer.

Adding compost to garden


Compost embraces yard waste such as grass clippings and leaves as well as food waste. Most people keep food waste in a bin until they have enough to bury beneath their gardens, which could take months to collect. Compost comes from plant-based foods, which nourish the roots of the plants. It removes toxins from the ground so the soil retains the nutrients it needs to flourish. The compost then decomposes back into the soil it came from.

Note: Growing basil loves well-rotted compost because it adds more nutrients to the soil.

Mulch for garden


Mulch is either organic or inorganic. You’ll know organic mulch due to the popular use of wood chips, straw, and shredded leaves. Inorganic mulch comes in the form of pebbles or gravel. The virtue of inorganic mulch is that it doesn’t leach the nutrients from the ground or return them. Mulch does:

    • Prevent the erosion of soil

    • Prevent weed proliferation

    • As it decomposes, it improves the structure of the soil

    • Regulates plant temperature

    • Helps the soil to retain its moisture and nutrients

Note: Basil is a cool-growing plant that receives its best support from shredded newspaper, leaves, grass clippings, straw, and some compost.


Fertilizer adds nutrients to the soil, much like a vitamin tablet does for humans. Fertilizers can be synthetic or organic, but they deliver the same nutrients to the soil. Since we’re discussing using spent coffee grounds as fertilizer for basil plants, we know that coffee is organic, and we know that the coffee plant gives us a wide range of vitamins and nutrients. 

Are Spent Coffee Grounds Fertilizer Or Compost?

The short answer is they’re both. Spent coffee grounds can be folded into the soil before planting. The two percent nitrogen content in used coffee grounds doesn’t add to the soil right away. Rather, it’s used by the microorganisms in a garden and then released into the soil. This delay in the addition of nitrogen into the soil isn’t enough to nourish plants. You’ll need a nitrogen fertilizer to make sure the plants are healthy. 

Paper coffee filters can be composted, too. Together, they’re known as “green” compost. To be fully effective, compost should have “brown” elements added to the “green” ones. This means grass clippings, leaves, paper, and straw should be mixed with the organic or food waste compost.

So there you have it. The soil needs added nutrients due to the nutrients it originally had being leached out of it by bad growing practices. Fertilizer puts these nutrients back into the soil so the plant can grow healthy and strong. Compost does the same. Mulch only covers the soil so that water and plant temperature is better controlled with no weed growth.

Basil leaves

The Nature Of Basil

Basil is an herb from the mint family. Often called sweet basil, it grows from one to three feet tall. It loves full sun, moist soil, and lots of organic fertilizer and compost (hello, coffee grounds.) The leaves are stunning medium green, oval-shaped, smooth with serrated edges, and grow about four inches. 

Basil, which began in India, has over 150 varieties, most growing in Asia. Its name comes from the Greek “basileus,” which means royal or king. Basil’s flavor is a cross between clove, mint, and anise. It can be grown indoors or outdoors, although the plant loves the sun and water (not too much, though, or you’ll get root rot.) If the temperature falls below 50 degrees Fahrenheit, the plant will die.

Basil In Medicine

Basil has been well-known for over 5,000 years for its medicinal uses as well as in cooking. While the Romans were adding basil to their wine for flavoring and preserving, the ancients used it to cure epilepsy. The ancients found that antibiotic, anti-inflammatory, sedative, diuretic, and digestive aids were just a few components of basil.

In fact, basil’s medicinal elements include soothing intestinal gasses, kidney problems, colds, and flu, acting as a laxative, lowering blood sugar, lowering cholesterol, and soothing joint pain. The herb is also known for killing the bacteria that cause food poisoning along with diarrhea.

Basil In Spirituality And Love

If you’ve ever been to a Greek Orthodox Church, you’ll have seen basil in the font as well as in pots beneath the altar. The herb was said to have grown outside the tomb of Christ after he arose. The herb is also said to strengthen those who fast for their religions. In the Near East, basil is planted on gravesites as a kind of passport to the other side. Some who have passed over even have a basil leaf on their breast.

In Italy, girls still to this day wear basil at their waists to announce their availability and as a sign of love. The herb is sacred in India, where it symbolizes faithfulness, love, and eternal life.

Basil on dishes

Basil In Food

Herbs and spices enhance the flavor of meats, vegetables, fruits, and sauces. Basil is good to add to meat rubs and marinades for beef, chicken, lamb, and meats of all kinds. It goes most excellently on eggs. Place the whole leaf on the pizza as a topping. You can shred basil into the soups you make from the leftovers of chicken, beef, bison, lamb, and other meats. The possibilities are endless.

I’m a huge believer in the “eat your medicine” maxim. I add herbs and spices to everything I eat, but none more than my vegetables and none more than basil. My health problems are all about inflammation, and I use my spices and herbs accordingly. I use dried herbs and spices bought from the grocery store, but fresh herbs are a little different:

    • Too soon. Adding basil too soon to dishes while cooking makes it go limp and your dish won’t get the full flavor of the basil. Instead, add it almost at the end of cooking to get the full Monty, so to speak

    •  Not enough. Dried herbs are very concentrated, so if you use fresh basil, you might not be using enough. Triple (yes, triple) the amount you’d substitute fresh for dried to get enough basil in your dishes

    • Oops. Using the wrong type of something in a family of hundreds is easy to do. With basil, sweet basil is the most common and what you find at the store or the Farmer’s market. It’s usually just labeled “basil.” Other types, though, are found in specialty shops or some farmers’ markets. Holy basil is very bitter and best when it’s cooked. Purple basil is best raw because it turns black as it cooks. Then there’s lemon and cinnamon basil, which needs no explanation. Make sure you buy the right stuff

    • No refrigeration. Some herbs, spices, and other foods are best when refrigerated. Not basil. It thrives in full sun, remember? Tuck it into a Mason jar in water out of direct sunlight, and your kitchen will not only smell amazing, but the herb will be fresh and ready to go when you need it

    • Say yes to the freezer. While basil might not like the fridge, it doesn’t object to being frozen. You have to do it right, though, to preserve all that incredible flavor:

**Remove the leaves from the stems

**Blanch them in boiling water

**Immediately dip them in ice water to stop the cooking process

**Let them dry

**Lay down layers of waxed paper or parchment paper. Place the basil leaves on the layers of paper, then place the whole thing in a freezer container like Tupperware

**The leaves will shrink a tad as they cook, so don’t use as many leaves as fresh

Basil In Food, Part 2

Now you know how basil reacts to cooking, it’s time to learn in what dishes to use basil:

    • Tomatoes. Pasta sauces, marinara, pizza sauce, chili, anything you use tomato for, you can use basil to season it

    • Pasta. Spaghetti, lasagna, fettucini, casseroles, soups, if it has pasta in it, you can use basil in it (even simple butter and noodles)

    • Pesto. Pesto can also be used in pasta dishes, salad dressings, and a dozen other things. Guess what it’s made out of?

    • Soups and casseroles. Basil is a robust herb, adding a peppery kind of taste to your soups, stews, and casseroles

    • Salads. Hey, basil is leafy and green, so salads are the perfect place for it, right? Actually, basil adds a kick to an ordinary salad, so eat up!

    • Sauces. Sometimes food just has to have a sauce in order to taste fantastic. Take barbecue sauce, for instance. Some finely chopped basil would jazz it up. A seafood sauce would benefit from a little basil, as would tartar sauce. I’m sure you’ve got the idea.

Basil FAQ

How Much Water Does Basil Need?

Basil needs one inch of water at all times. It’s a thirsty little guy, but you want to avoid root rot, so only an inch. Basil in containers will need more frequent watering because the goal is not to have dry soil.

Does Basil Need Full Sun?

Yes. It’s a tropical plant requiring lots of sun. If you have a spot in your yard that gets six to eight hours of sun every day, that’s where to place your basil plants. In the South and Southwest, that’s a little too much, so afternoon shade is essential to the plants’ survival. Make very sure the soil drains well.

How To Prepare Soil For Basil?

Place your compost or coffee grounds as fertilizer around the plants. Make sure the coffee isn’t clumping, because that prevents proper drainage.