Transplanted some ivy from the boundary fence to the West facing house wall. If it attaches itself it should insulate the house in summer and winter and soak up some of the rain running down the wall. I calculate the section is getting around twice the rainfall it would naturally get due to rooves, driveways and wall runoff. The problem is that while its way too wet in winter, in summer the extra water would actually be beneficial. The more I think about the problem the more I think some kind of winter/summer valve system is needed. Once the forest is established the roots should drain the section deeper and the plants transpire more.