Q.Is There a Gardener Out There That Specializes in Hibiscus?
I just bought my first two trees and already have problems with pests and yellow leaves. Help?
Certified GKH Gardening Expert
Treating the plants with neem oil should help with controlling the pest problem. It will also help in treating any fungal-related issues that may occur. Here is additional info on neem oil: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
As for the yellowing, this is probably stress related and most likely due to the pests. This article may also help: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/answers-to-what-causes-hibiscus-leaves-turning-yellow.htm