Coffee Grounds For Peace Lilies ( 7 Pros & Cons )

Peace lilies are renowned for their adaptability as houseplants, which might lead you to consider alternative care methods, such as using coffee grounds. You might have also come across the idea that coffee grounds can benefit indoor plants, particularly as a fertilizer. But is this truly effective for peace lilies?

Coffee grounds can benefit your peace lilies, primarily as a fertilizer due to their rich nutrient content. Additionally, these grounds are acidic, which can help lower the pH of your soil. Using coffee grounds in your potting mix can also act as a deterrent for indoor pets like cats and aid in addressing leaf browning issues in peace lilies.

Coffee Grounds Benefits For Peace Lilies

Recently, I’ve delved into the topic of homemade fertilizers and composts for your indoor plants. Creating your own can be particularly advantageous because you have full control over the nutrient balance your plant receives. Moreover, it’s often cost-effective compared to store-bought alternatives and can be an enjoyable DIY project.

Coffee grounds have been a popular choice for naturally enhancing houseplants, including peace lilies. If you’ve ever wondered about the reasons behind this, let me provide some insights. If you want to know how to make soil for your peace lilies then check out my recent article Peace Lily Soil ( Fast & Easy ).

Nutrients In Coffee Grounds

Your used coffee grounds serve as an excellent nitrogen source, which is a crucial nutrient for many houseplants. Peace lilies, in particular, thrive when they receive a balanced combination of nitrogen, phosphorous, and potassium. While you could opt for store-bought fertilizers, using readily available coffee grounds is a sustainable and cost-effective alternative worth trying.

Coffee Grounds Contain Organic Matter

In addition to their nutrient content, coffee grounds contribute organic matter to your peace lily’s soil. Incorporating organic materials into the soil of your peace lily can have multiple benefits, such as enhancing aeration, increasing water retention, and improving drainage. If you want to use your peace lily as an air purifier then check out my recent article Peace Lily Air Purifier ( True Or False? ).

Coffee Grounds Increase The Acidity Of The Soil

Plant soil can vary in pH, being either acidic or alkaline (basic). Understanding this difference is important because some houseplants thrive in more acidic soil while others prefer a higher alkaline environment.

Now, when it comes to coffee grounds and your peace lily, not all grounds are created equal. To increase the acidity of your soil, you should use unwashed coffee grounds, as they have a higher acidity level. Additionally, it’s best to incorporate the coffee grounds into the soil promptly, rather than waiting for several days or weeks. Fresh grounds are more effective at adjusting the pH.

Peace lilies typically thrive in soil with a pH ranging from 5.8 to 6.5, which falls within the acidic range (anything below 7.0 is considered acidic). Therefore, coffee grounds are a suitable choice to maintain your peace lily’s preferred soil pH. If you want to know how to care for your peace lilies during the winter then check out my recent article Peace Lily Winter Care ( In 7 Easy Steps ).

Coffee Grounds Contain Microorganisms

Were you aware that certain microorganisms, like earthworms, can actually benefit your houseplants? It’s true!

These earthworms consume organic matter as it begins to break down. What’s even more beneficial is that, as these earthworms move through the soil of your peace lily, they enhance aeration.

Now, you don’t necessarily have to go digging in your yard to find earthworms to introduce into your plant’s soil, unless you’re particularly inclined to do so. Using compost that includes organic materials and leaf litter should be sufficient to attract earthworms to your indoor garden.

However, as I’ve mentioned before, some indoor gardeners might not be enthusiastic about the idea of live bugs wriggling around in their home within the plant soil. If you fall into that category, that’s perfectly okay.

Of course, your peace lily can thrive without earthworms, and there are plenty of alternatives available. But if you’re comfortable with them, they can truly be a valuable addition.

Cons Of Using Coffee Grounds For Peace Lilies

While there are several advantages to using coffee grounds for peace lilies, it’s important not to overlook the potential disadvantages. These can include slowed growth, excessive water retention, fungal growth, and increased risk of pest and insect infestations. It’s essential to weigh both the pros and cons when considering coffee grounds as a plant care option.

Slower Growth Rate

Adding coffee grounds to your soil can lower its pH, especially if it’s already acidic. Peace lilies typically thrive in soil with a slightly acidic pH range. However, if the pH drops too much due to excessive coffee grounds, it can potentially slow down the growth of your peace lilies. It’s essential to monitor the soil’s pH and adjust the use of coffee grounds accordingly to maintain an optimal environment for your plants.

Higher Risk Of Overwatering

Coffee grounds, when used as organic matter, can act like a sponge and increase the risk of overwatering your peace lilies due to their water-retention characteristics. However, this issue can be addressed by adding coarse or perlite soil to modify the soil composition. This adjustment will enhance water drainage and reduce the risk of overwatering your plants.

Mold And Fungal Growth

Using coffee grounds directly on the soil can create a favorable environment for fungal diseases, leading to mold formation that can harm your plant. To reduce these risks, it’s better to use coffee grounds as part of your composting process rather than placing them directly on the soil.

How To Use Coffee Grounds For Peace Lilies

Now that you have a better understanding of why peace lilies benefit from coffee grounds, you’re likely eager to save your coffee grounds and incorporate them into the care of this flowering houseplant.

Coffee Grounds As fertilizer

Considering all the fantastic benefits of coffee grounds, they serve as an excellent natural fertilizer for your peace lily. This fertilizer contains the essential nutrients your plant requires, helps maintain the desired acidity level in the peace lily’s soil, and ensures proper soil aeration and water drainage to prevent waterlogging, which can harm your plant. It’s worth noting that, in comparison to some other fertilizers, coffee ground fertilizer releases nutrients more slowly. This means it won’t provide an immediate nutrient boost to your peace lily upon application but will gradually nourish it over time.

While the exact timeline can vary depending on various factors, you should typically begin to observe the positive effects of using coffee grounds on your peace lily within two to four months.

To start using your homemade fertilizer, simply save your coffee grounds from your morning coffee routine. Alternatively, you can purchase coffee grounds from a store and apply them directly to the peace lily’s soil. Spread a thin layer of grounds over the soil surface. As you continue to care for your houseplant and water it, the fertilizer will naturally work its way deeper into the soil, benefiting your peace lily as it does so.

Coffee Grounds Are Excellent At Keeping Pets Away From Your Peace Lilies

Peace lilies are unquestionably stunning, and while you may enjoy gazing at them, it’s crucial to ensure that your cats or dogs don’t come into close contact with these plants.

The peace lily, scientifically known as Spathiphyllum, is toxic to both cats and dogs.

In dogs, ingesting the plant can trigger an inflammatory reaction, leading to swelling in the upper airway, throat, tongue, and mouth. Cats, on the other hand, may experience an upset stomach and mouth irritation.

While moving the peace lily plant out of your pets’ reach can help protect dogs, cats are agile climbers and jumpers, making it challenging to keep them away from your indoor garden.

Fortunately, placing coffee grounds on top of the soil can deter your cat from approaching the plant. Additionally, you may want to consider using mothballs to further discourage your cat from nibbling on your peace lily.

Coffee Grounds Can Fix Brown Leaf Tips For Peace Lilies

Coffee grounds may potentially help alleviate peace lily leaf browning and other discoloration, but the effectiveness depends on the underlying cause.

If you tend to overwater your houseplant, a common mistake among beginners and even experienced plant owners, the leaves may turn brown or yellow. The same applies to underwatering.

To avoid any confusion, it’s advisable to water your peace lily weekly, ensuring the soil is moist but not overly saturated. If you notice slight drooping of the plant, it’s a clear sign that it requires water.

Excessive sunlight exposure can lead to leaf browning, as can the use of the wrong type of fertilizer or one with a high nutrient concentration. Overusing fertilizer is another factor that can cause brown tips on your peace lily’s leaves.

Coffee grounds may help address fertilizer-related issues, but they won’t resolve problems caused by improper lighting and watering practices. Therefore, it’s crucial to pinpoint the specific cause of your peace lily’s leaf browning before considering coffee grounds as a solution.

Coffee Grounds Will Keep Pests And Insects Away

Coffee grounds can serve as a natural pest repellent due to their high caffeine and diterpene content, which are effective in deterring pests. If you’ve already planted your lily, whether indoors or outdoors, you can use coffee grounds to create a protective barrier. Simply sprinkle them around your lilies to establish a defense against pests, snails, and other creeping insects.

How To Prepare Coffee Grounds For Peace Lilies

You can prepare coffee grounds for use on your peace lily in several ways: as a mulch, as a liquid fertilizer, and as a component of natural compost. The first two methods are relatively quick and straightforward, while composting takes a bit more time and patience.


Mulching is a technique often associated with outdoor plants, but it can benefit indoor plants like your peace lily as well. This process entails spreading a uniform layer of organic material over the soil surface. The organic matter serves as a reservoir for water, encourages the growth of beneficial bacteria and microorganisms, and also functions as a natural fertilizer.

To create a mulch mixture, combine materials like wood chips, leaves, branches, and even straw with a small amount of coffee grounds. Be mindful of the quantity of coffee grounds you add to ensure it doesn’t significantly affect the soil’s pH.

Liquid Fertilizer

Using coffee grounds as an organic fertilizer not only enhances plant photosynthesis but also acts as a natural deterrent for harmful insects. The great news is that used coffee grounds are equally effective for this purpose. Here’s how to create a liquid fertilizer using coffee grounds:

Materials needed:

  • Five gallons of water
  • Two cups of used or unused coffee grounds
  • A watering can
  • A filter
  • A spray bottle

To prepare this fertilizer, simply dilute the coffee grounds in the five gallons of water. Use a filter to strain the mixture, ensuring it’s free of any larger particles. You can then apply this homemade coffee ground liquid fertilizer as a foliar spray or a soil drench to nourish your peace lily.

  1. Prepare the Mixture: Begin by adding five gallons of water to a watering can. Then, incorporate two cups of coffee grounds into the water. Mix the liquid gently and let it sit overnight.
  2. Dissolve the Grounds: Ensure that the coffee grounds are fully dissolved in the water. This step is crucial as undissolved grounds can clump together, potentially creating a barrier that restricts water flow to your plants, which can be detrimental to their health.
  3. Apply to Soil: Use this homemade fertilizer by pouring it into the soil around your plants. This nourishes the root system and enriches the soil.
  4. Foliar Application: If you want to care for the foliage, strain the liquid to remove any larger particles, then transfer it to a spray bottle. Apply the liquid directly to the leaves and stems of your peace lily.

This homemade coffee ground fertilizer provides your peace lily with essential nutrients and can be applied to both the soil and foliage for overall plant health.


You can create organic compost using leftover coffee grounds, along with items like old leaves, grass clippings, eggshells, and food scraps. To make natural compost suitable for mature outdoor peace lilies, combine these materials with 40% coffee grounds. This compost should be applied only two to three times a year for optimal results.

For indoor peace lilies, you can modify the compost mixture by reducing the coffee content by 10% to 20%. This adjustment tailors the compost to the specific needs of indoor plants.

How Much Coffee Grounds To Add To Peace Lilies To Be Effective

You’ve collected your coffee grounds for your peace lily, but you’re uncertain whether you have enough or if you might inadvertently harm your houseplant.

Balancing the right amount is crucial. Too little fertilizer could lead to nutrient deficiencies, while excessive amounts can harm the plant, often reflected in the condition of the leaves.

So, what’s the appropriate quantity to use? If you typically generate about a pot of coffee grounds from your morning brew, this should be a satisfactory amount to nourish your peace lily.

You can either add it all at once or introduce it gradually. If this is your first time using coffee grounds, I’d recommend starting with a modest amount and observing how your peace lily responds. You can then increase the quantity if everything seems to be going well.

How Often To Use Coffee Grounds For Peace Lilies

Just like monitoring the quantity of coffee grounds you use as a peace lily fertilizer, the frequency of fertilization is equally significant. Some indoor gardeners apply the equivalent of one pot of coffee grounds each month and find success with this schedule, while others choose to fertilize less frequently, perhaps every couple of months.

The variation in timing is due to the fact that every peace lily has distinct needs during different stages of its growth and dormancy.

If you’re unsure about which method to start with, consider marking your calendar to assess your peace lily’s condition every two months after applying the coffee grounds. This way, you can reevaluate your peace lily’s requirements and make informed decisions.

When winter arrives, it’s advisable to fertilize your plant every six weeks. This regimen sets your peace lily up for a healthy and prolific spring and summer, which are its natural growing seasons.


What is the best fertilizer for a peace lily?

To ensure the health and abundant production of attractive spathes, feed peace lilies with a well-balanced fertilizer, like one with a ratio of 10-10-10 NPK, or slightly higher in nitrogen. In fertilizer formulas, NPK represents the proportions of nitrogen, phosphorus, and potassium elements in the mixture.

Do peace lilies like eggshells?

While some suggest incorporating eggshells into your houseplants to provide calcium, it’s not a quick solution for your Peace Lily. Eggshells decompose slowly and release their nutrients over an extended period – think decades, not months.

Do peace lilies like tea?

You can enhance the humidity and deter spider mites by spraying your plant’s leaves with compost tea. Simply transfer it into a spray bottle and mist the plant’s foliage. This not only benefits the plant but also keeps spider mites at bay.

What flowers should you not put coffee grounds on?

In general, coffee grounds are too acidic to be directly applied to soil, even for acid-loving plants such as blueberries, azaleas, and hollies. Coffee grounds can hinder the growth of certain plants, including geraniums, asparagus ferns, Chinese mustard, and Italian ryegrass.