I've had a beautiful hibiscus for almost two years that has been blooming a lot. I water when the soil feels dry to the touch, but now the leaves are starting to turn yellow and are falling off.
Certified GKH Gardening Expert
This happens a lot with hibiscus plants. This article should help: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/answers-to-what-causes-hibiscus-leaves-turning-yellow.htm