If you see tiny insects with a soft, cottony appearance, typically on the undersides of leaves, stems, and even in the soil, you may have a mealybug infestation in your hands. While they may seem harmless, the presence of mealybugs can weaken your plants. Common remedies against mealybugs include neem oil, insecticidal soap, and even introducing natural predators like ladybugs. However, an eco-friendly and readily available solution gaining traction is the use of coffee grounds.
Coffee contains two ingredients that repel pests: caffeine and diterpenes. While most of us know what caffeine is, diterpenes may be something we’re less familiar with. Diterpenes are a class of terpenes unique to coffee. Terpenes are plant compounds that have been studied for their antimicrobial, insecticidal, and weed-control properties. So, beyond perking up your mornings, the byproduct of your morning java can prove to be a powerful ally in the battle against pesky mealybugs.
Signs of a mealybug infestation include the white, or grayish substance resembling bits of cotton or wool that the bugs secrete. Mealybugs feed on plant sap, leading to stunted growth in affected plants. They also extract vital plant nutrients, causing leaves to turn yellow. Mealybugs excrete a sugary substance known as honeydew as they feed. The honeydew attracts ants that work to protect the mealybugs, and also creates a conducive environment for the growth of sooty mold on the plant surface. Good thing there are coffee grounds you can use as a quick and reliable solution against mealybug infestations.
Using coffee grounds to eliminate mealybugs
There are two ways you can use coffee grounds to get rid of mealybugs. First, you can make a coffee grounds spray. Simply combine a tablespoon of dry used coffee grounds with one cup of water in a spray bottle and mix well. Allow the mixture to infuse overnight. Test the solution on a small section of leaves to ensure plant compatibility. If no adverse reaction is observed, spray the solution on the affected plant liberally to create a protective barrier against mealybugs. You may also apply the spray directly to the soil around the stem and roots to prevent mealybugs from infiltrating the ground.
Second, you can use coffee grounds as an ant deterrent. Since ants depend on pests like mealybugs for the honeydew they love, they protect the pests from natural predators. Combat this secondary issue by sprinkling a layer of coffee grounds (the texture and smell repel ants) evenly, approximately half to one inch thick (or more, depending on the level of ant activity), over your garden soil. Regularly refresh the coffee grounds, especially after rainfall or strong winds for optimum effectiveness. While both methods are safe and natural, note that their application will leave the scent of coffee on your plants and the soil. To prevent re-infestation, maintain plant hygiene. Regularly inspect your plants for pests, and consider companion planting as a complementary solution.
