Directing gutter water to where you want it! Water will naturally take the path of least resistance (even if that means around your home's foundation). Dig a trench about 3'-4' wide and about 8" deep. Line it with black plastic (to discourage weeds) and fill up to ground level with 3/4" to 1/2" mixed gravel. You want the gravel to stay put, be easy to walk on, direct the water, but not compact. Now you have a gravel path you can walk on, that will also drain excess water away to plants!
Choosing fruit trees - US There's a reason I loved flipping through Organic Orcharding before we got our farm --- it's a great book to dream by. Or, if you want to pretend you're being scientific, you can use the excellent charts for variety selection. For example, Logsdon recommends starting your orchard planning by learning which species do well in your climate. The map above hits the highlights.
The Six Pests Plaguing your Fruit Trees - and How to Control them Organically