The Best and Worst Plants for Coffee Grounds in Your Garden
You’ve just brewed your morning cup of Win Win Coffee, rich, warm, soul-soothing. As the last drop drips into your mug, you do what many of us do: eye the soggy pile of used grounds in your brewer and wonder, “Should I just toss this in the trash?”
Wait. Not so fast.
We’ve all heard the advice: Coffee grounds are great for your garden! And sure, it sounds eco-friendly and even a little poetic, your morning ritual giving back to the earth. But here’s the thing: not all plants love coffee as much as we do.
Let’s dig into what’s true, what’s not, and how to use coffee grounds the right way in your garden.
From Bean to Basil: My First Coffee Compost Mistake
I still remember the first time I tried using coffee grounds in my garden. It was spring, the air smelled like promise, and I was feeling inspired after reading a blog that claimed coffee grounds were “miracle mulch.” Naturally, I went all in, dumped a full French press’s worth around my tomatoes and basil.
Big mistake.
Two weeks later, the basil leaves were yellowing, and the tomato plants looked like they’d seen better days (like, pre-caffeine days). I learned the hard way that while coffee grounds can be amazing, there’s a right way and a wrong way to use them.
Let’s make sure you skip the heartbreak.
So… Are Coffee Grounds Actually Good for Plants?
Yes, but with some caveats.
Used coffee grounds are rich in nitrogen, which is great for soil health. They also improve drainage, water retention, and aeration in compost. Plus, worms love them. And if worms are happy, your soil is happy.
But here’s where it gets tricky: coffee is acidic, especially before brewing. Once brewed, most of that acidity goes into your cup, but the grounds can still lower the pH of your soil over time, especially if used in large quantities.
That’s why moderation is key.
Plants That Love Coffee Grounds
Here’s a quick list of plants that will give you a grateful little fist bump (or root wiggle) for feeding them your leftover grounds:
Blueberries – Acid-loving and thriving.
Azaleas and Rhododendrons – Say thank you with more vibrant blooms.
Hydrangeas – Coffee can influence their color—more acidic soil = bluer flowers.
Carrots and Radishes – Mixed into the soil, grounds help these root veggies flourish.
Camellias – Big fans of slightly acidic environments.
Plants That Would Rather You Didn’t
Some plants are more sensitive and don’t enjoy the extra nitrogen or slight acidity:
Tomatoes – A little goes a long way, but too much coffee can stunt their growth.
Lavender – Prefers alkaline, well-draining soil—coffee makes it grumpy.
Geraniums – Coffee grounds can actually inhibit their growth.
And definitely don’t dump fresh (unbrewed) coffee grounds directly onto any plant bed. That’s like force-feeding an espresso shot to a toddler. It’s too intense.
How to Use Coffee Grounds the Win Win Way
We like to say, “What’s good for the bean can be good for the garden”, as long as you do it thoughtfully.
Here’s how:
✅ Compost it: Mix your used grounds into your compost pile with other organic materials like fruit scraps, leaves, and paper. It balances the “green” and “brown” components for healthy decomposition.
✅ Mulch it (lightly): Sprinkle a thin layer around acid-loving plants. Don’t pile it too thick, or it can create a barrier that water struggles to penetrate.
✅ Soil mix booster: Combine with potting soil or garden dirt to improve texture and nutrients.
✅ Pest control: Sprinkle grounds around plants to deter ants, slugs, and snails—nature’s tiny caffeine haters.
Our Community Garden Story
A couple from our Win Win Coffee community in Portland shared this gem: they started using their daily grounds from our Sunbeam Blend in their compost bin last year. Come spring, their hydrangeas exploded into bloom, bluer and fuller than ever. “It’s like they had a cup of coffee with us,” they said.
It reminded me of why I love this journey. Coffee isn’t just about that morning energy boost, it’s about connection. To each other, to the earth, to rituals old and new.
Final Grounds for Thought
So yes, coffee grounds can be good for your garden. But just like brewing the perfect cup, it takes balance, care, and a little bit of experimentation.
Before you toss your grounds, think of them as the second act of your brew. With the right plants and a little know-how, your garden can sip right along with you.
And if you’ve tried gardening with coffee, I’d love to hear your story. Shoot us a message, we might just feature your garden (and your favorite blend) in an upcoming post. 🌱☕
Until next time, keep sipping, keep growing, and remember: when you share coffee, you share life.
