Are Coffee Grounds Good for Indoor Plants?

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If you have an indoor plant or two, you probably wonder what the best way to care for them is.

You know that proper air circulation is crucial to their health, but you want to be able to enjoy them as well.

At the same time, you realize that plants need optimal drainage to avoid the buildup of toxins.

Coffee grounds may seem like a natural way to keep your plants happy, so can they be used safely?

Coffee Grounds Are Great for Plants, But Only If They are Fresh

The first thing you need to be aware of is that coffee grounds are not generally a good choice for plants.

The coffee grounds you might have had sitting in the bottom of your cup or pot for days is no longer beneficial for your plants.

The reason they are so harmful is that after the coffee beans have been roasted, leftover oils and solids settle to the bottom.

When you use them in your plants, these oils get on your plants and can be easily washed off by water.

The bad news is that these oils will actually do more harm than good.

They cause leaf burn, which keeps your plant from taking up water, and it can even make them susceptible to air pollutants.

The good news is that you can still use coffee grounds for your plants, but only if you use them right away.

If your coffee is recently brewed, you can dump the grounds directly onto your plant.

It is better to use the grounds in a watering can than to throw them on your plant because it will help keep them from getting all over.

Coffee Grounds Can Provide Beneficial Nourishment to Your Plants

The reason you should avoid old coffee grounds is because of the leftover oils. However, fresh coffee grounds can be healthy for your plants.

Coffee grounds are high in nitrogen, so they will make your soil more acidic and improve drainage and aeration. The benefit from the nitrogen is that it will make it easier for your plants to grow their leaves, flowers, and fruits.

Coffee grounds are also rich in micronutrients. The high nitrogen levels means that there is less room for other nutrients, but what your plants do get is high-quality nourishment. They are rich in calcium, magnesium, and potassium, which are all beneficial for fruit production.

Coffee grounds are a great addition to compost piles. They are already partially rotted and can serve as food for worms and other microorganisms in a pile, contributing to the process of turning food waste into soil.

How to use Coffee Grounds on Plants

Coffee grounds can be used in 1 of 2 ways. The first is to simply bury the beans (remember to remove any non-ground coffee beans first) in the soil of a plant. The second is to put the grounds into the water you use to water your plants.

Coffee Grounds in Soil

If you plan on putting the grounds directly into your soil as fertilizer, do it once every 2 weeks or whenever you water a plant. Of course, you can put the grounds directly into potting soil, but if you prefer to use your own dirt, just mix a few tablespoons of grounds into the soil before planting.

Do not use coffee grounds in place of all types of fertilizer, however. For example, if you’re using compost or fertilizer with higher nitrogen content, you’ll want to avoid adding coffee grounds. They’ll only serve to make the soil too rich and will inhibit plant growth.

If you’re worried about the beverage’s acidity, don’t be. The actual pH is somewhere around 6.0, which is slightly acidic, so it won’t change the pH level of your soil too much.

Coffee in Water

If you want to use coffee grounds in the water you use to water plants; the easiest way is to add a few tablespoons of grounds into a watering can and then fill it with water. You can then use this mixture to water your plants.

Do not add coffee grounds to a spray bottle unless you plan on keeping the grounds in there all the time. Due to the small area, coffee grounds can quickly build up and clog the spout.

If you add the grounds to water and don’t plan on using them right away, make sure your coffee grounds are completely dry before you put them in a closed container. Otherwise, they’ll trap moisture, and the grounds will grow mold or simply reabsorb the water again.

If you want to add coffee grounds to a spray bottle, try soaking the grounds in water in a container first. You can then use this mixture of 1 part coffee and 4 parts water as a general-purpose spray for your plants. Spritz this mixture on the tops of leaves, or use it to wipe away dust if you have dusty plants.

To kill any potential bugs, combine 20 oz of water with 1 oz of your favorite dishwashing liquid and add coffee grounds to the mixture. Let it sit for 24 hours, and then spray the solution on your plants.

You can also use coffee grounds to repel bugs by mixing a few tablespoons into the soil of affected plants. Or you can combine an equal amount with cayenne pepper to create a spray that’s good for repelling a number of types of bugs.

Coffee grounds have the added benefit of smelling great, so you may find that your plants benefit from the scent. At the very least, you can rest easy knowing that your plants won’t smell like dirt!

What Kind of Coffee Grounds Should You Use?

There are two different types of coffee grounds that you can use, including:

1. Dried Coffee Grounds

Dried coffee grounds are the ones that you will find at home. They have been dried out and can be used directly in your plants.

2. Fresh Coffee Grounds

Fresh coffee grounds can be used to add nitrogen to your compost pile. While you can use them directly in your plants, they will have a stronger smell.

How Much Coffee Grounds Should I Use?

It is best to check the recommendations on the back of the coffee packages before using them on your plants. You should also take note that you will need to use a lot more coffee grounds than you would use compost. You should avoid using fresh coffee grounds since this will make your plants smell bad.

How Can You Find The Right Plants To Use Coffee Grounds?

There are several plants that you can use coffee grounds on, including:

1. Carnation

If you want to use coffee grounds on carnations, then the dried coffee grounds will be most effective in controlling the soil pH.

2. Rose

If you want to use coffee grounds on your roses, then they are best when mixed with fertilizer.

3. Azalea

The acidity of the coffee grounds may be too much for azalea plants, so you should not use them on this type of plant.

4. Shrubs

Coffee grounds can be beneficial for shrubs, which is why they are often used in shrub borders.

5. Ivy

Coffee grounds can be used on ivy, but you should try to use a diluted solution. You should also try to avoid using fresh coffee grounds instead of dried ones.

6. Geranium

You can use coffee grounds on geranium plants, but you should avoid using fresh coffee grounds as the smell can be too much for some plants.

7. Coleus

Coleus plants can be planted with or without coffee grounds, but it is recommended that you use them in the soil.

8. House Plants

You should keep the coffee grounds away from house plants since they may cause root damage and affect the soil pH.

9. Fungus

If you want to prevent fungus, then you should use coffee grounds in your flowers. They can also be useful in controlling the soil pH.

Problems With Using Coffee Grounds To Fertilize Indoor Plants

There are problems that you can have with using coffee grounds to fertilize your plants, including:

1. Mold And Mildew

Some molds and mildews can grow, which is why you need to make sure that the coffee grounds are dry before using them.

2. Smell

The smell of the coffee grounds may be too much for some plants, but it is not as bad as fertilizer smells.

3. Solutions

You can try to use the old coffee grounds instead of watering your plants too much, allowing the plant to absorb the water from the grounds. You can also try to use coffee grounds that have been dried and cooled down for a day or two before using them.

Final Thoughts On Using Coffee Grounds

Using coffee grounds in your plants can be a good thing or a bad thing. It all depends on the type of plant that you are growing and what kind of soil that you are using. If you want to use coffee grounds, then you should make sure that they will be beneficial for your plants and not hurt them. Make sure to use coffee grounds in moderation, and you should be able to get the most out of it.