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Coffee Grounds in Your Garden: Which Plants Love a Coffee Boost?

September 12, 2023

I am not the only one in my garden who loves coffee

What plants love coffee? If you’ve ever asked yourself that question as you want to your garden in the early morning with a cup of coffee, today I thought I’d answer it. We will dive deep into a topic that combines two of our favorite things — gardens and coffee. We are referring to the popular gardening hack of using coffee grounds to enrich your soil and give your plants a boost. Let’s explore which plants thrive with a sprinkle of coffee grounds and how to use them appropriately in your garden.

Watch our “Coffee Grounds & Cardboard” in th Garden Video by Master Gardener Steve

Understanding the Benefits of Coffee Grounds

Before we delve into the specifics, it’s important to understand why coffee grounds can be beneficial for your garden. Coffee grounds are rich in nitrogen, a mineral that is essential for plant growth. They also contain other nutrients and minerals like potassium, phosphorus, and a host of micronutrients that can nourish your plants. Moreover, coffee grounds can help improve soil structure and attract beneficial microorganisms and earthworms.

Plants that Like Coffee Grounds

Not all plants will appreciate a coffee-infused soil; some plants thrive in the slightly acidic to neutral pH that coffee grounds offer. Here’s a rundown of plants that would love a coffee boost:

  1. Acid-Loving Plants: Azaleas, rhododendrons, and blueberries love acidic soil, making them great candidates for coffee ground mulch.
  2. Tomatoes: Though not strictly acid-loving, tomatoes can benefit from the nitrogen boost that coffee grounds offer.
  3. Carrots and Radishes: These root vegetables seem to enjoy the extra kick provided by coffee grounds.
  4. Roses: Roses love slightly acidic soil, making them another perfect candidate for this kind of mulch.

How to Use Coffee Grounds in Your Garden

Now that we know which plants like coffee grounds, let’s look at how to use them effectively:

  1. As a Mulch: Sprinkle used coffee grounds on the soil surface as a mulch. This not only adds nutrients to the soil but also helps in retaining moisture.
  2. In Your Compost: Add coffee grounds to your compost heap. They are a great source of nitrogen, which helps in breaking down organic matter faster.
  3. As a Fertilizer: Mix coffee grounds with other organic materials to create a balanced fertilizer. Try using a ratio of four parts other materials to one part coffee grounds to avoid creating soil that is too acidic.
  4. Pest Repellent: Surprisingly, coffee grounds can also be used to repel pests. Sprinkle grounds around areas where you have seen slugs and snails to keep them at bay.

🐾 Bonus Tip – Deter Cats and Pests Naturally

Used coffee grounds may help deter neighborhood cats or curious critters. Their scent is unpleasant to many animals, making them a natural, non-toxic repellent when sprinkled around garden beds or entry points. Just reapply after rain and avoid overloading areas to prevent water retention problems.

⚠️ Use with Care—Avoid Overuse

Although coffee grounds are a valuable soil amendment, moderation is key. They tend to form a moisture-retentive layer if applied too thickly, which can impede air flow and trap excess water, potentially leading to fungal issues. A thin sprinkle or a 1:4 mix with organic materials (leaves, shredded cardboard) is ideal—this maintains soil balance and prevents clumping. Regularly monitor soil pH and texture to ensure your garden benefits from coffee-ground enrichment without unintended side effects.Is coffee for your garden??

Repurposing coffee grounds in your garden is not just a sustainable choice, but also a boon for certain types of plants that thrive in slightly acidic soil rich in nitrogen. By knowing which plants like coffee grounds and using them correctly, you can give your garden a healthy, hearty boost. So the next time you brew a pot of coffee, think twice before discarding those grounds; your garden may thank you for it!

Do you use coffee grounds in your garden? Share your experiences and tips in the comments below! Happy gardening!


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