I live in zone 6 and when I brought my potted hibiscus tree inside for the winter I noticed that the trunk and limbs are covered with small bumps under the wood. Sort of like acne. It is still flowering but a lot of the leaves are turning yellow and dying. The tree is 25 years old. What can I do to treat the issue, or has it life come to an end?
Potted Double Braided Hibiscus Tree
Certified GKH Gardening Expert
It is hard to tell without seeing the tree in person, but the bumps could be scale insects or Nectria fungus. In both cases, the bumps could be scraped off. Scale is treatable, while Nectria is a sign that the tree is dying from the inside.
If the bumps are instead woody growths from the tree instead, I'm not really sure what they could be. Perhaps asking at a garden center is the best option.