It depends what part of NJ, skiekitty. Northern NJ is rocks and tree roots. Near the shoreline is sand. Further south is the pine barrens. It is a small state, with lots of variety. I am just over the border from NJ in the mountains. They call this area "the slate belt."
Maybe your ground cover rose needs some time to take off. Mine were planted last spring, but didn't start sending out long canes until this summer.
