I remember when I first shared the idea of adding coffee grounds to garden soil, my mom, who’s into gardening herself, thought I had gone crazy. I mean…it’s pretty unconventional to say the least…
But, believe me when I say this, the results spoke for themselves!
In today’s article, we’ll be going through a carefully curated list of flowers that can benefit from coffee grounds. Let’s jump straight into it, shall we?
Before You Start – Tips & Precautions
You can get soil testing kits from the internet easily like Amazon, or make a trip to your local gardening supplies store to acquire them. It may seem like an extra hassle, but it pays off to know exactly the kind of soil quality and potential deficiencies you’re working with.
Besides coffee grounds, you could also incorporate natural amendments like wood ash. Take a look at our full guide on how to use wood ash to boost plant growth naturally.
Flowers That Thrive With Coffee Grounds
1: Azaleas
Azaleas love acidic soil for growth. Mixing in coffee grounds with the soil can help raise the acidity levels as a whole and promote vibrant blooming.
2: Rhododendrons
Like azaleas, rhododendrons too prefer acidic conditions for optimal growth and can substantially benefit from a nutrient boost provided by coffee grounds.
3: Hydrangeas
Some hydrangea varieties can bloom pink or blue flowers depending on the acidity or alkalinity of the soil. By incorporating coffee grounds in the garden, you’ll raise the acidity of the soil, potentially causing your hydrangeas to bloom blue flowers exclusively.
If you’re curious about the science behind it (and how to do it naturally), take a look at our guide to changing hydrangea color naturally.
4: Gardenias
This fragrant flowering plant thrives in acidic conditions and can bloom extremely well with a nutrient boost from coffee grounds.
5: Camellias
Camellias are typically known for their foliage, but also offer blooms that stand out. These perennials can absolutely benefit from a coffee ground boost, aiding with quicker flower turnover and lush foliage development.
6: Roses
As strange as it may sound, roses are quite the nutrient-hungry plants. They need nutrients from all sources, and nitrogen from coffee grounds can provide them with a substantial boost. They’re also susceptible to pests, and coffee grounds can help keep those creepy crawlies at bay.
7: Hostas
Hostas, like roses, are relatively more susceptible to slugs and other pests. Therefore, sprinkling some coffee grounds around the plant base and even mixing in some with the soil to give it an acidic boost can be a good idea.
8: Lily Of The Valley
This delicate perennial can benefit from coffee grounds by absorbing acidic nitrogen and using the nutrient boost to produce more blooms more vigorously.
9: Begonias
Coffee grounds contain a good blend of nitrogen, potassium, and phosphorus, which are all the essential nutrients begonias need for optimal growth and flowering.
10: Marigolds
Not only are marigolds excellent for warding off pests and insects from the garden, but they also enhance overall soil structure and do relatively well in slightly acidic soil conditions.
If you’re looking to reinforce your pest control game, take a look at our guide on natural garden sprays that keep bugs away without chemicals.
11: Daffodils
I’d suggest keeping your daffodils indoors or in hanging baskets and mixing in small amounts of coffee grounds with their base soil for some nutrient enhancement. Just don’t do this too frequently, or else overly acidic soil can ruin your daffodil roots.
How To Use Coffee Grounds In Your Garden
Let’s Conclude
As stupid as my mom thought I was for suggesting adding coffee grounds to the garden soil to “improve” it, over time, she too learned that this method definitely has some merit. It may not work for all flowers, but it does work for those that benefit from some extra nitrogen boost.
And if you’re in the mood for even more clever tricks to make gardening easier and more effective, don’t miss our roundup of genius gardening hacks.
That said, I will still suggest you conduct a soil test before going about mixing coffee grounds into your soil. It will help identify any imbalances in the soil and give you a clear understanding of the soil quality you’re working with.
Do I havevto dry out coffee grounds before adding to soil. I ve been throwing the days used ground in a jar wet then adding to my soil and my potting mix. Am I wrong?
Hi Deb! You’re not wrong at all! 😊 You can add used coffee grounds directly to your soil or potting mix even if they’re still a bit wet. They’ll dry out quickly once mixed in, and the nutrients will still benefit your plants. Just avoid piling up thick, soggy layers to prevent mold (which is why I usually recommend drying them out first, but it’s totally optional). 😊
I really like all of your helpful hints. Do you have all of this in a book?
Hi Trenna! Thank you so much, I’m really glad you find the tips helpful! 😊 We don’t have a book, but you can easily download and print the articles right from your phone browser. Just tap the browser’s menu (usually the three dots or lines), choose “Share” or “Print,” then select “Save as PDF” or send it to a printer if you have one connected. That way, you can keep all the info handy while you garden! 😊
Hello, I’m wondering about coffee grinds and crushed egg shells for hydreadras plants?
Hi Sue! 😊 Crushed eggshells and coffee grounds can both be helpful, but in small amounts! I sprinkle dried coffee grounds lightly around my hydrangeas for a nitrogen boost, and crushed eggshells add a bit of calcium. Just be careful not to overdo it, too much can mess with the soil pH. A little goes a long way!