It’ll make your skin crawl when you realize that the mound of powdery white stuff on your plant is a cluster of mealybugs. These pests prefer protective areas of plants, which are often those hard-to-reach crevices you don’t always get to take a good look at. Mealybugs will drink up sap from your plants and release sticky honeydew, leaving your plants weakened and moldy. The good news is that you can stave off these gross little bugs by planting herbs they don’t like, like thyme, rosemary, and lavender.
This particular trio of herbs can do a world of wonders for your garden when it comes to mealybugs, though they can also help with many other pest troubles you have. These aromatic herbs keep mealybugs away with their smell, their antimicrobial properties can prevent honeydew from growing mold, and their oils have insecticidal properties. They also attract predatory insects that turn mealybugs into a meal-y bug — making great progress on depleting the population in your garden.
Herbs do more than flavor your food
While you enjoy the warm, comforting flavor of fresh rosemary and thyme on your roasted vegetables, mealybugs are dying at the hands of these plants in your backyard. Rosemary oil, thyme, and thyme oil have all been found to be anti-microbial, meaning they will prevent the growth of fungi, bacteria, and viruses and repel various insects, including mealybugs. Rosemary oil may be the best way to kill mealybugs if repelling them isn’t enough since the New York State Integrated Pest Management program found mealybugs to have a 90 percent mortality rate when exposed to the oil.
Lavender is another mealybug fighter, though you might think this pretty herb, often posing as an ornamental, is only good for attracting ladybugs. A 2024 study published in the Journal of Insect Science found lavender oil to be toxic to mealybugs and other pests, though it’s not as effective as other options in the study.
Attract predatory insects with flowering herbs
Where lavender lacks as a mealybug repellant and killer, it thrives as an attractor for predatory insects. Mealybugs make a delicious feast for a variety of helpful bugs like lacewings, minute pirate bugs, ladybugs, and spiders. The plethora of lavender flowers will bring in plenty of ladybugs. Pair it with dill to attract even more beneficial insects, including ladybugs and some lacewings. Lavender benefits edible gardens and flower beds, easily drawing in the good guys wherever you need them.
Thyme is attractive to hoverflies when they flower, who also like to feast on mealybugs. Though rosemary is better off repelling pests, it will bring in plenty of pollinators once it goes to flower, making it worth your while to have it in the garden. Keep rosemary, thyme, and lavender near your edible garden to keep pollinators and predators nearby while keeping problematic mealybugs away.
