Do Hostas Like Coffee Grounds?

Hostas are easy to grow plants that favor the shade best and come back year and year again. Just like any plant, Hostas will do even better when given a little bit of extra tender love and care. One foolproof way to give your Hosta a little bit of extra attention is by introducing fertilizers, like coffee! But do Hostas like coffee?

Hostas love coffee grounds. Using coffee grounds as a fertilizer works very well in making a Hosta a very healthy plant. But, be careful! Everything is good in moderation, too much coffee can harm or even kill a Hosta. It’s also important to note that not all coffee grounds work.

See below to find out even more about how coffee can benefit your Hosta. We’ll cover everything from how coffee can benefit the plant to how exactly you use coffee on your Hosta and so much more!


What Does Coffee Grounds Do For a Hosta?

We know that Hosta love coffee grounds, and that coffee grounds offer a variety of benefits to the plant. But what exactly do coffee grounds do for a Hosta plant?

There’s four major things coffee grounds do for Hosta plants. Let’s look at each one below in more detail.

Hostas Are Large Plants

Hostas are large plants, meaning they consume more nutrients then other plants will. A major nutrient this plant consumes is nitrogen.

Nitrogen is a key factor in plant growth and actually supplies plants with the energy they need to be able to grow. Luckily, coffee grounds contain a lot of this nutrient.

Coffee Grounds Attract Earthworms

Earthworms absolutely love to eat coffee grounds, so coffee grounds are excellent at attracting worms to the soil of a Hosta. But why are worms important to the growth of the Hosta plant?

Well after a worm eats the coffee grounds they produce ‘castings’ which is a fancy word for worm poop. Castings are packed with important nutrients that the hungry Hosta uses to grow.

Worms also dig tunnels which helps for multiple reasons. These tunnels provide aeration and improve the drainage system which keeps the roots from rotting away due to an unhealthy build up of water in the soil.

Coffee Grounds Balance pH Levels In the Soil

Coffee grounds help the pH in soil to stay at the perfect rate for Hosta plants which is between 6.5 and 6.8 pH.

This is important because it determines if the soil is in the right condition to maintain the nutrients needed to keep plants alive.

Coffee Grounds Repel Pests

Coffee grounds also repel pests.

Some include:

  • Beetles
  • Fruit flies
  • Other insects

Not only because it contains caffeine which most insects can’t stand, but also because when scattered around the plant on top of the soil it serves as an abrasive presence that can damage the insects exoskeleton.

Now that we know a few reasons why coffee grounds help Hosta to grow so much, let’s learn more about something previously mentioned, the repellent of pests. The worst pest a Hosta gardener will deal with is the slug.

How Do I Use Coffee Grounds for My Hosta?

There’s multiple ways to properly use coffee grounds for your Hosta plant that will guarantee success. The three key questions to think about when considering this addition to your garden is the when, where and how.

Let’s take a look at the chart below for more information:

When do I add coffee grounds to my hosta?

The best time to add coffee grounds to a hosta is the start of spring.

How do I add coffee grounds to my hosta?

Combine cooled, used coffee grounds with compost and mulch.

Where do I add coffee grounds to my hosta?

The best place to add coffee grounds to your Hosta is to use the mulch/compost mix as topsoil around the plant.

Now that we know the how, when and where let’s find out if coffee grounds have any negative effects on the Hosta plant. Read further to find out.

Can Coffee Grounds Harm Hostas?

We’ve gone over all the benefits of ground coffee to Hostas, and we’ve even touched base on how exactly to use coffee grounds to see these benefits happen right before our eyes. But can coffee grounds harm Hostas?

Coffee grounds can harm Hostas, using coffee grounds excessively can cause numerous negative effects such as stunting the plants growth, causing root rot and injuring the plant by using hot coffee grounds.

Adding too much coffee grounds as topsoil can stop water from getting into the soil which will cause the thirsty plant to wither up and die but can also trap water in the soil which will lead to the roots rotting away. Hot coffee can injure a plant’s stems, leaves and roots, and the combination of all these things cause the plants growth to be stunted or even lead to death of the Hosta.

Do Coffee Grounds Keep Slugs Away From Hostas?

It’s common knowledge in the gardening community that some creatures like to make plants into a snack. This type of damage to roots, flowers and leaves can cause a plant to wither and eventually die. The same thing goes for Hostas, which happen to be one of the slug’s favorite meals. But luckily coffee grounds keep slugs at bay.

Coffee grounds are excellent in keeping slugs away. But the reason why coffee grounds work so well in keeping slugs away is the same reason why only certain types of coffee work. Slugs hate caffeine.

Decaffeinated coffee won’t work in the war against slugs. But caffeinated coffee will not only deter or slow slugs down, but will actually kill them entirely after prolonged exposure.

Keep reading to learn how to apply this slug defeating elixir to your own garden.


Ground coffee has multiple benefits to a hostas overall health. It provides multiple nutrients, deters harmful pests such as slugs and more, attracts positive helpers like earthworms, helps in both aeration and drainage which all leads to a happy, healthy plant.

But remember to use coffee grounds correctly, and sparingly or else you’ll end up with a sick or dead hosta.