If you love coffee and gardening, you’d be glad to know that you can make the most of your everyday brew for your little indoor garden. In this article, you will learn about what coffee grounds do for your plants, how they benefit your plants, how to use them correctly and efficiently in your garden, as well as knowing which plants highly benefit from the use of coffee grounds.
Coffee grounds are an efficient source of nutrition for plants, but they must be used in moderation. Houseplants like Philodendrons, Jade Plants, Christmas Cacti, Cyclamen, and African Violets grow best with the use of coffee grounds.
What Do Coffee Grounds Do?
Coffee grounds act as a natural fertilizer for plants. They have often been used in composting and outdoor gardens due to the benefits they provide in keeping the soil healthy. They are acidic but do not change the pH levels of the soil when added.
Coffee grounds give out nitrogen. It is important to plants since it is a major component of chlorophyll. With the right amount of nitrogen, plants will grow and develop better. There are three forms of soil Nitrogen:
- Organic Nitrogen
Majority of the Soil Nitrogen is made up of Organic Nitrogen
- Ammonium (NH4+)
NH4+ positive ions bind with the soil’s negative ions in a Cation Exchange Complex (CEC) and practically behave like other cations in the soil.
- Nitrate (NO3–)
NO3– negative ions do not bind with the soil due to the principle of “like charges repel”, instead they dissolve in soil water and precipitate as soluble salts.
Soil nitrogen is primarily made up of 95% Organic Nitrogen that comes from either plant or animal residue. Whereas plant nitrogen is common in inorganic forms such as Ammonium (NH4+) and Nitrate (NO3–).
Plants require large amounts of nitrogen, and even if nitrogen is readily available in the atmosphere, the whole process of absorption can take some time. For plants with restricted root systems due to compaction, nitrogen deficiency will be evident.
When nitrogen deficiency occurs in plants, their stems get thinner, their leaves lose color and their growth is stunted. When there is little to almost no nitrogen being absorbed by the plant, it will eventually die.
In addition to nitrogen, coffee grounds also contain a good amount of phosphorus and potassium to keep your plant healthy.
Can You Use Coffee Grounds as Potting Soil?
No, don’t use coffee grounds as your soil.
As stated above, coffee grounds can be a beneficial addition to your compost mix. In some cases, a little sprinkle of coffee grounds directly on your plant’s soil can help too.
But in almost all cases, it’s not a good idea to use coffee grounds as the potting medium.
Using coffee grounds instead of soil will make the plant medium too acidic for most houseplants.
Adding a little to your compost or fertilizer mix can be quite beneficial though.
Benefits of Using Coffee Grounds
Seasoned gardeners say that coffee grounds solve all kinds of plant issues and have been used for various plants in different settings.
- Reduce Plant Disease
The natural microorganisms found in the coffee grounds prevent the growth of most pathogenic fungi that would cause plants to rot.
- Deter Pests
Although pests may not be too much of a problem indoors, it would still be worth mentioning that the use of coffee grounds deter pests that may cause harm to your plants. They are especially effective against slugs.
- Improve Soil Quality
When the grounds decompose, the nutrients are released. These micronutrients are nitrogen, phosphorus and potassium. They are great fertilizers that eventually help your plant grow better. The process may take some time, so do not expect quick results.
- Water Retention
Indoor plants don’t really need to be watered that often, having said so, the use of coffee grounds in your houseplants allow you to water them even less. Thus making your job a lot easier.
- Provides Drainage
In the event you are the type who may have watered the plants a bit more than required, coffee ground break down the soil and avoid any stagnant water that may cause rotting in your plant’s roots.
- Keeps Cats Away
For cat owners, this would be quite ideal. The use of coffee grounds discourage your feline friends from using your plant beds or pots as litter boxes.
Through these points, we can definitely say that coffee grounds are quite advantageous, but you would need to use them in moderation. After all, too much of anything can be disastrous in the end.
Where to Get and How to Store Coffee Grounds?
If you are not a coffee drinker but would want to try out using coffee grounds in your little indoor garden, you can easily get some at any of your local coffee shops. It’s free and quite abundant wherever you go. All you need to do is ask. Some big names in the business actually re-pack these grounds and display them in their store, free for anyone who needs them.
Tips in Using Coffee Grounds in Your Indoor Garden
Using the coffee grounds properly is quite important. Too many coffee grounds may eventually poison your plants, it is always about moderate use. Here are some tips on how to use coffee grounds efficiently:
- Don’t Use Coffee Grounds for Seedlings
The amount of nitrogen, phosphorus and potassium in coffee grounds are quite high for young plants. It would be best to use them by the time you have already repotted your seedlings, or if they have already matured.
- Mix With Your Mulch
Mulch is basically a layer of material placed on the surface of your soil in order to provide nutrition and insulation. Although coffee grounds have a great amount of micronutrients that are readily available for plant consumption, it would be best to mix the grounds with mulch rather than directly mixing it with the soil. This process allows the elements in the grounds combine well with the soil.
- 1:3 Ratio
As mentioned, coffee grounds should be used in moderation. You can mix the grounds directly with the soil but it won’t be as effective compared to using it with mulch. In order to do so effectively, a ratio of 1 part coffee ground to 3 parts of soil should be followed. This is only to be done with soil that does not have any plants in them yet, since mixing the grounds and soil deeply would cause physical damage to the root system of your plant.
- Water After Application
After you have applied enough coffee grounds to your potted plant, experts suggest that you lightly water the soil in order to actively mix them in together. The water helps the grounds, soil and mulch to bind well.
- Use Sparingly
Especially when intended to be used in a small container or pot, coffee grounds must be used in small amounts. A tablespoon would be enough for a small plant. You only need to cover the top portion of your soil with a thin layer of coffee grounds.
By following these tips, you will definitely be able to make the most of the coffee grounds you have at home.
Houseplants That Thrive with Coffee Grounds
If you are looking for a more organic method of fertilizing your plant, coffee grounds are definitely the best choice. However, not all plants would grow well with coffee grounds due to the amount of nitrogen they produce. Here are some indoor plants that would thrive with the use of Coffee Grounds:
- Philodendrons (Philodendron bipinnatifidum) The use of coffee grounds is excellent in keeping the veins of the Philodendrons strong and flexible.
- Jade Plants (Crassula ovata) The use of coffee grounds in the soil of Jade Plants promote thicke stem growth and better water retention.
- Christmas Cacti (Schlumbergera spp) By using coffee grounds for cacti and succulents, you are able to manage a good drainage system to avoid any stagnant water that would ultimately kill your plant through rotting. The micronutrients found in coffee grounds also encourage blooms.
- Cyclamen (Cyclamen hederifolium) Succulents are great houseplants. With little coffee grounds mixed into the soil, the plant flourishes with lush green leaves and winter blooms.
- African Violets (Saintpaulia spp) These plants absolutely love nitrogen and acid. They will therefore thrive in soil sprinkled with coffee grounds, just be sure not to get coffee on their leaves.
Most of the plants listed here thrive in acidic soils. Although we have mentioned that the chances of coffee grounds changing the pH of your soil would be close to impossible, most coffee grounds are acidic. Being part of the entire soil system, will contribute to the acid needs of the plant itself.
How Often Should You Use Coffee Grounds in Your Houseplant?
With the amount of organic material available in coffee grounds, there is no doubt that it will be quite beneficial to use for your indoor garden. But you don’t have to put them on your plant’s pot every day. This would cause an imbalance in the nutrients they get and would eventually harm your plant. Ideally, you can add a spoonful of coffee grounds to your plants every 4 to 6 weeks. This amount would be more than enough for your houseplant. Being that the consistency of the grounds is quite fine, you would not need that much to maximize their benefits.
Coffee grounds have been used for outdoor vegetable and fruit gardens for the longest time. Harnessing the benefits brought about by this supposed waste can truly change the way we grow our gardens at home.