Hi, I planted a "Mexicola Grande" avocado, probably the cold-hardiest avocado around, at my parents' home in Walnut Creek. A family friend has had the same tree for 25 years, there's another large avocado tree in the same neighborhood (not sure of the variety), and we've gotten fruit from another friend's very large, old tree (again, a different variety with small fruit) a couple of miles away. So in general, they should grow here. We planted a cold-hardy variety so we wouldn't ever have to worry about frost. Cold seems to have nothing to do with this particular problem. At first I thought it was heat, but that also does not seem to be it.
Ever since we planted the tree last May, when it was big and had thick, waxy leaves, it has not grown an inch. The same leaves are still on the tree, slowly getting greyish, dry tips that have crept inwards from the tips to about a third of the way down on each leaf. The tree looks like it's always just about to burst into growth but never does. The tree is planted on a slight slope, with a large drainage pipe underneath, and significant soil amendment, as I know they don't like heavy clay soil. Drainage seems good. On either side of the tree, they have a healthy sapote tree and a healthy macadamia tree. Any ideas why the avocado is just sitting there and what's causing the leaf problems?