Hi there I live in Nanaimo BC and live in a regular new subdivision that was built on a mountainside. Above me are houses that tower above and I was looking to create some good ( atleast some ) privacy. Leylandy Cypress grow fast and tall from what I have read. I would be planting the "privacy barricade" behind one of these allan block retaining walls with a fence set about another 3' behind. I would like the trees to grow in front of the fence but I certainly don't want the roots to push the wall over as the tree grows. At the narrowest point the distance between the fence and wall is 2'. Is Leylandy a good choice or are there others?