Q.Use of rocks for fill in a planting area
I built a retaining wall 3 ft high X 25 ft wide at the base of an area slanting down to the wall. In the yard are a lot of stones and rocks that I would like to use for fill before putting dirt in the deeper area. Will that work for growing? Will the rocks draw and become a habitat for snakes? I live in the SE US.
It sounds like you have essentially created a kind of rock garden and there are a wonderful number of plants that do well in this kind of garden. This article can help get you started:
Yes, this type of structure in the garden will attract snakes. But this is not a bad thing. Most snakes are benign if left alone and can do a wonderful job of keeping out unwanted pests from the garden.