We all want our boxwoods to be thick, lush, and that perfect shade of vibrant green. To get there, your *Buxus sempervirens* needs the right nutrients. When it comes to feeding these shrubs, the “more is better” approach definitely doesn’t work, but neglecting them isn’t an option either. They can be a bit picky about their fertilizer, but here’s a pro-tip: your morning cup of joe might be exactly what they’re craving.
The Good Stuff in Coffee Grounds
Even when your boxwood blooms, it isn’t actually looking for phosphorus (the stuff that usually boosts flowers). Instead, it’s hungry for nitrogen and potassium. These two are the secret sauce for vigorous growth and those deep green leaves we love. Coffee grounds happen to be packed with both! The only real catch is whether you drink enough coffee to keep up with your garden’s appetite. If you have a massive hedge, your kitchen scraps might not be enough, and you’ll need to supplement. However, for a potted boxwood, your daily brew should provide plenty of nutrients.
Prepping Your Grounds for the Garden
Coffee grounds are free, organic, and a favorite among seasoned gardeners. But don’t just dump those soggy grounds straight from the filter onto your plants! Wet grounds can get moldy fast, which isn’t great for your soil. Instead, spread the damp grounds out flat on a plate or tray and let them air dry completely. Once they’re dry, you can use them immediately or store them in a sealed container for later. Just a heads-up: if you see even a speck of mold, toss them out—don’t use them as fertilizer.
How to Feed Your Boxwood with Coffee
During the growing season, you can treat your boxwood to a coffee boost about once a week. Here’s the best way to do it:
- Only fertilize during the active growing season.
- Stick to a once-a-week schedule.
- Always use dry grounds.
- Sprinkle them evenly around the base of the plant (the root zone).
- Gently work them into the top layer of soil with a hand rake.
- Give your boxwood a good watering afterward.
- Pro-tip: Alternatively, you can stir the grounds directly into your watering can.
Keep an Eye on Soil pH
As much as boxwoods love the nutrients in coffee, there is one downside: coffee is acidic. Boxwoods prefer a more neutral pH, ideally between 6.5 and 7.5. You don’t have to stop using coffee grounds, though! Just mix the grounds with some rock dust (stone meal), which helps neutralize the acidity and adds extra minerals. It’s still a good idea to test your soil pH every now and then. If it starts dipping too low, you can raise it back up by adding lime. For boxwoods, calcified seaweed (Algenkalk) is a fantastic choice.
Quick Tip:
Calcified seaweed isn’t just great for minerals; it’s also a powerhouse for preventing boxwood blight and can even help ward off various pests.
