Q.how to sanitize soil
Both potting (I have too much to microwave, et al) and soil in raised bed. All of my veggies have pests and disease. I cut off affected areas and have an organic pest/disease treatment. I used it once, but waited too long to spray again. Actually, I wondered about interval times. Directions said only use up to 6 times.
How about solarizing your garden beds? Here is a link to an article with tips on how to do this: