Hi - Do you have advice on when to spray apple, pear, cherry, & peach...
Hi - Do you have advice on when to spray apple, pear, cherry, & peach trees? Also, I've heard olive or canola oil can be used as an oil spray. If this works, how much per gallon should I use? Thanks. Steve Sturm
Delaware County Ohio
Good to hear from you! Most fruit trees need to be sprayed on a regular basis. An excellent reference is the OSU Extension bulletin #780, "Controlling Diseases and Insects in Home Fruit Plantings." You can purchase a copy of this bulletin from OSU Extension Office in Delaware County. Follow this link to their website: http://delaware.osu.edu/
Regarding Olive or canola oil, I have not seen any data of their efficacy. In addition, I do not think it is labeled as a pesticide. Hence, we cannot recommend it. You are very welcome to call master gardener volunteers in Delaware County Extension office.