I'm envious of your backyard orchard. We just don't have the room but I keep a few apple trees active. Like you, I dont want to spray but I also know that it's very challenging to keep apples pest and disease-free naturally as there are a host of problems ranging from fire blight to insects that keep commercial orchards spraying over a dozen times a year. I too have always felt that at least a home orchard would requre at the very least – a few treatments of something, starting with an oild spray and then a more thoughtful and strategic program of pest management. At least, I could control what was sprayed. That said, I havent sprayed my apples (I have a disease-resistant espalier fence planted with 'Liberty' which usually does fine but this is on a very small scale. I suggest trying to contact Fedco Seed's proprietor John Bunker in Maine – I hear that he had some great ideas an methods on controlling disease and reducing spray programs – especilly with heirloom varieties. Good luck!