Q.Why are the leaves on my jade plant wrinkled
Plant gets south sun. It is a large plant
Certified GKH Gardening Expert
This can happen for a few reasons, depending on if it is in container or outside. Over, and underwatering can do this. If this was moved into the sun recently from a darker spot, then this can cause it as well.
Last will be temperature. Sometimes if the temps are low, this can cause what you are seeing.
Here are some articles that will help: https://www.gardeningknowhow.com/houseplants/jade-plant/jade-plant-care.htm
https://www.gardeningknowhow.com/houseplants/jade-plant/pests-of-jade-plants.htm