Hi Mary, I worked at a Garden Nursery for 3+ years and when customers would come in inquiring about warding off stinkbugs we offered them two different options. One of them was Praying Mantis eggs. You can purchase the eggs and then place them in the nook of a tree close to your garden. When they hatch they find their food source in your garden and the local area. People who came back would give us positive feedback about the Praying Mantis eggs. Another option we would offer is Kaolin clay. We did not sell Kaolin clay but if people were interested we referenced this article for more information. https://hoke.ces.ncsu.edu/2013/08/con...
Hope this helps!