In my experience, the most common causes of Jade plant (Crassula ovata) leaves turning yellow or brown is due to ...

A reader's 10-year-old jade plant may have yellowing leaves due to changes in the soil makeup or a spider mite infestation.

Jade plants are some of the all-time favorite succulents ... Signs that jades are overwatered are mushy leaves that become yellow and drop. Allow potting soil to dry between infrequent waterings.