3 Ways To Reuse Coffee Grounds To Liven Up Your Garden

If you're a gardener and an avid coffee drinker, listen up. While you absolutely should not be putting coffee grounds in your garbage disposal, they can do more than keep your fridge smelling fresh — they can help liven up your garden. Food Republic spoke with gardening expert Luke Hammond, farmer, educator, and Seedtime director of brand advancement, and he shared three ways you can reuse those soaked-through grounds.

First up? Composting. "Coffee grounds are rich in nitrogen (about 2% by volume), making them an excellent 'green' component for compost," he told us, adding that they "balance out 'brown' materials like leaves or straw and help accelerate decomposition."

Hammond also mentioned using coffee grounds as a pest repellent, citing anecdotal evidence that their texture and caffeine content can be unappealing to slugs and snails. "They can be sprinkled in a thin layer around vulnerable plants," he informed us, but only in limited amounts. 

His third suggestion for improving your garden involves using the grounds as mulch or a soil amendment. When used in thin layers or mixed with other organic materials, coffee grounds can help to retain soil moisture and suppress weeds.

This isn't a green light to start dumping your coffee grounds into compost bins or garden beds daily. While Luke Hammond noted that concerns about acidity are often overstated ("Most of the acidity is removed during brewing," he said), there are still some potential issues to be aware of — especially when it comes to using them in excess. "When applied directly in large amounts, grounds can form a dense layer that impedes water and air movement," Hammond cautioned. Since most garden plants prefer soil that drains well and gives roots room to grow, you don't want to block those pathways.

Finally, Hammond warned that coffee grounds can potentially inhibit seed germination. "Some studies show fresh grounds may inhibit growth of seedlings or small plants," he said. So if you're direct-sowing seeds, you might want to skip that bed when applying coffee grounds. Conversely, if you're transplanting seedlings and there's a bed that has been treated with the remains of your morning joe, it's better to plant them in a different space.