As you know, in Ontario we can’t use commercial pesticides on residential property. I have two apple and one nectarine tree. What would you recommend I use in all the stages of fruit development so I can achieve the maximum yield?
Fruit trees can indeed be a rewarding addition to a home garden. To ensure the maximum fruit yield your are aiming for it is important, as you mention, to prevent diseases, which often can affect fruit trees. The most important step to achieve this is to follow good cultural practices to ensure healthy tree growth. You will find them outlined in this article Fruit Trees in the Home Garden by OMAFRA (Ontario Ministry of Agriculture, Food and Rural Affairs) and this post to a similar question of our website. The OMAFRA article also recommends preventive measures available under the cosmetic pesticide ban.
I hope you will enjoy your trees and their fruit for many years.