Q.How Do You Trim Hibiscus
How would I do this with a Hibiscus Tree? Trim back the plant – Trimming back the plant allows the plant to focus on regrowing its roots. In perennials, trim back about a 1/3 of the plant. In annuals, if the plant is a bush type, trim back a 1/3 of the plant. If it is a plant with a main stem, cut off half of each leaf.
Certified GKH Gardening Expert
The same concept applies for trimming hibiscus--cutting by a third. These plants generally regrow and fill out rather quickly. This article may help you as well: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/tips-for-pruning-hibiscus-plants-when-to-prune-hibiscus.htm