My problem is little typical and I have done everything to solve it but haven't got any success. I am guilty of using malathion pesticide on my hibiscus and I came to know quite late that malathion is toxic for hibiscus. Ever since I used it, my hibiscus stopped growing and flowering. It's been three years and it's in same condition as in the snap I have uploaded. It's a yellow colored hybrid variety. I even pruned it down last year to reduce the burden on plant but have been seeing just little growth and that too on tips. One thing I noticed is the tips of branches are quite thick and I don't know why is it so. Please help me take my plant out of this shock. I am losing hope.
Hibiscus Growth Problem!
Certified GKH Gardening Expert
I am not sure why this hibiscus is still reacting to the Malathion after so long. I suspect it also has a zinc deficiency, which causes tiny leaves, pale green or yellowish patches on the leaves, and little or no growth. A gardening store may be able to provide you with a zinc spray such as zinc sulfate. This should help the plant start growing again.
If you aren't already, follow these instructions for removing 1/3 of the plant per year when pruning: