Q.Althea Rose Of Sharon Has Strange “elongated” Growth This Year
I have several Althea Rose of Sharons at varying levels of maturity, and for some reason this year nearly all seem to have strange, long/thin top growth. There do appear to be the start of some buds, but nothing like I have normally seen over the past 4-5 years. I did some pretty aggressive pruning in late winter, so not sure if that has anything to do with it? Or if pests or disease may be affecting my normally robust shrubs?

Certified GKH Gardening Expert
Many times, this is a response to lack of light. This can be due to shading from large trees, or other structures that have been erected, recently.
It should not cause much trouble, but they may appear to "droop" with age.
Here is an article that will help you to care for the shrub:
https://www.gardeningknowhow.com/ornamental/shrubs/rose-of-sharon/rose-of-sharon-bush.htm