5 Ways to Use Tea Leaves In Your Garden, From Fighting Weeds to Boosting Soil

There are many household items you can use to improve your plants and outdoor spaces, like Epsom salt to promote foliage or baking soda to freshen up garden decor. Another natural trick is using tea leaves to nurture plants and deter unwanted pests, among other benefits.  

Tea leaves provide natural acidity to plants that enjoy the boost and can bump nitrogen levels when added to compost. But be wary of using any tea leaves that have soaked up milk or added sweeteners, which can do more harm than good. Read on to see how our experts use tea leaves in their own gardens and discover how your afternoon cup just might benefit your plants. 

Speed Up the Compost

Recycling is a big part of Lindsay Etemadipour’s daily life, and it's no different when it comes to the herbalist and founder of Symbi’s leftover tea leaves. "I make three to four cups of tea a day and add the leftover tea leaves to my compost,” Etemadipour says. “This allows for more nitrogen in my pile, which is what speeds up the decomposition.”

Sue Ure, a homeware designer and gardening expert in the southwest of France, is an enthusiastic tea drinker and her used tea bags go straight into the compost bin, as well. "I use tea bags more often than loose tea and try to buy ones that are compostable," she says. "It turns out most tea bags, like almost everything else, contain microplastics. If you aren’t sure whether your teabags are plastic-free, it’s best to compost the tea and discard the bag."

Ward Off Weeds

While used tea leaves may not directly help ward off weeds, sowing them into a healthy mulch is a surefire trick to keep the weeds at bay. A thick layer of mulch prevents seeds from reaching the soil and smothers out the sunlight for any weeds that have already buried themselves. 

Boost Nitrogen Levels

Another option that is beneficial for the garden is adding the tea leaves directly into your garden soil. "This can help increase the nutrient content, encourage beneficial microbial activity, and even improve soil structure," says Etemadipour. "The leaves are also slightly acidic, which is great for acid-loving plants. I swear by adding the tea leaves to my roses specifically." When her plants need a bit of extra support, Etemadipour might also add leftover tea by re-steeping tea leaves and using the second, weaker cup directly in her garden.

Ure also recommends adding tea along with the leaves if the plant enjoys the extra dose of nutrients. "When I drink loose tea, I might well empty the remainder of any cold tea, along with the leaves, onto a large azalea I’ve got growing just outside my kitchen door," Ure says. "Camellias, rhododendrons, and azaleas are all acid-loving plants and will appreciate an occasional top dressing of your leftover tea—but like all things, it’ll appreciate it more in moderation."

Fight Off Fungus

Some plant fungal infections can be fought naturally, and adding a diluted cup of chamomile tea to a spray bottle can do wonders for plants both indoors and out—but be sure the solution has cooled before application. To employ tea leaves in this application, let your used leaves sit in water and continue to steep until a weak brew is achieved.

Feed Your Worms

A healthy earthworm population in your garden has several benefits, from enhanced soil structure to heightened nutrients. The best way to encourage earthworms is to feed them nutrient-rich compost regularly, and adding your used tea leaves to the compost is a simple way to boost its organic structure.