Getting Rid Of Ficus Thrips

Q: I was given a ficus tree as a wedding gift 32 years ago. I keep it inside during the winter, but the rest of the year, it lives outdoors. Three years ago, leaves started curling up, which I learned was caused by ficus thrips. I’ve considered heavily pruning it back and getting rid of the infested leaves.

A: We have to take special care of this heirloom! Living outdoors is good because natural predators love to eat thrips. When you take the plant inside for the winter, spray the whole plant with horticultural oil or neem oil, making sure every surface is covered. Frankly, oil spray will kill only about half of the thrips population, leaving the other half of the crowd happily sucking sap from the leaves. If you want better control, use an insecticide that contains imidacloprid, such as Bonide Systemic Houseplant Insect Control. This will likely kill some of your beneficial insects, but your ficus will be protected for a year. Next spring, don’t use the insecticide, so your beneficial buddies will enjoy fresh thrips for the outdoor season.