Coffee Affection is reader-supported. When you buy through links on our site, we may earn an affiliate commission. Learn more.

Are Coffee Grounds Good for Hydrangeas? What to Know!

hydrangea flowers

Hydrangeas have long been considered to be an excellent choice for landscaping and plant lovers everywhere, and you can spot Hydrangeas in many people’s yards as you drive by in the springtime.

They are common in several locations, including parks, gardens, residential areas, and commercial locations.

However, if you’re a professional who plants Hydrangeas for a living or an amateur just getting started, you’ve probably heard that coffee grounds are good for Hydrangeas.

So, are they? And if they are, how are they good for the fragrant flower? Coffee grounds can be good for hydrangeas, but avoid adding them to potted plants. We’ll answer this question and more below.

divider 6

Are Coffee Grounds Good for Hydrangeas?

Used coffee grounds have been used to amend the soil of plants, and Hydrangeas are no exception. Coffee grounds have been used to change the color of Hydrangeas to a very pretty blue.

It seems that the nitrogen in the coffee increases the acid content of the soil surrounding the Hydrangeas, keeping them a gorgeous blue. However, it also brings out the colors in the pink, white, and purple hues of the gorgeous flowers.

Not only do the used coffee grounds help the flowers, but they are also good for the soil in which your Hydrangeas are planted.

shovel with coffee grounds to fertilize the lawn
Image Credit: Janet Worg, Shutterstock

Tips for Using Coffee on Your Hydrangeas

While used coffee grounds are suitable for your Hydrangeas, you can’t just walk out to your garden and pour coffee grounds or brewed coffee into the soil of your flowers.

Luckily, we have a few tips to give you on using coffee for your Hydrangeas in the section below.

Choose the Right Plant

While you can use ground coffee for your Hydrangeas, it works best on certain varieties of plants, especially if you’re looking for that vibrant bluish hue.

The lacecap and mop head varieties thrive when coffee grounds are added to their soil.

Use the Right Coffee

As there are different varieties of Hydrangeas that respond best to coffee grounds, there are certain types of coffee that work best as well.

Coffee changes your soil’s acidity, resulting in blue flowers on your Hydrangeas. Therefore, it’s best to go with a slightly acidic coffee. Remember, once you add coffee grounds to the soil and change the acidity, you need to do that regularly for the best results.

hydrangea flowers
Image Credit: Hans, Pixabay

Can You Put Coffee Grounds in Potted Hydrangea Plants?

While using used coffee grounds in your garden can be beneficial to your Hydrangea plants, it’s best to avoid putting them on potted plants, not just Hydrangeas.

There are two reasons that it’s best to avoid using coffee grounds in this way. First, coffee grounds have a strong aroma, especially when they’re wet or moist. Hydrangeas benefit from moist soil, meaning your potted plant could start stinking pretty quickly.

Second, fungi and bacteria can easily and quickly grow on moist coffee grounds, which you want to avoid on your plants and home.

How Often Should You Add Coffee Grounds to Hydrangeas?

If you compost your coffee grounds, then add them whenever you add compost to your garden, instead of other forms of compost.

It’s best to add them when the growing season begins, which is usually around spring. You can also add the grounds again in the middle of summer. Adding compost two to three times every year is usually sufficient for the flowers to be happy and vibrantly gorgeous.

However, if you’re not going to compost the coffee grounds, you can add a few cups a week. This, of course, is according to the size of the Hydrangea bush. You don’t want to go overboard and end up hurting the bush instead.

In fact, it’s best to invest in a pH meter to measure the acidity in the garden to determine if you need more or fewer coffee grounds to keep it healthy. It’s best to keep your pH levels between 6 and 6.5 for the best results with your plants, and a pH meter can help you judge how far off or how close you are to those numbers.

coffee grounds for compost
Image Credit: jokevanderleij8, Pixabay

What Are the Benefits of Using Coffee Grounds for Hydrangeas?

There are a few benefits of using coffee grounds on your Hydrangea bushes.

Of course, you know that the coffee grounds can heighten and even change the color of your Hydrangeas, but did you know there are other benefits to using used coffee grounds in your garden?

  • Ensures better moisture retention, which Hydrangeas love
  • Improves the quality of the soil in the garden
  • Rich in nitrogen, which helps the leaves, blooms, and stems of the plant
  • Can be good for earthworms, which in turn helps improve the quality of your soil
  • Improves the drainage of your soil if the coffee grounds have been composted

divider 2

Final Thoughts

So in answer to the question, “Are coffee grounds good for Hydrangeas,” the answer is yes. However, it’s best not to use them on your potted plants. It’s also best to invest in a pH meter to determine the pH levels before and after you use the coffee grounds as well.

You may also be interested in: 

Featured Image Credit: DeltaWorks, Pixabay


Kate MacDonnell

Kate is a lifelong coffee enthusiast and homebrewer who enjoys writing for coffee websites and sampling every kind of coffee known to man. She’s tried unusual coffees from all over the world and owns an unhealthy amount of coffee gear.

Read more

Related posts

Other Categories