Btw, VF on your tomato seed packets stand for two different soil-borne fungal diseases, Verticillium wilt and Fusarium wilt.
Down here in Florida we sterilize the soil if those things get going in our gardens, by solarizing (which is basically covering the soil with clear plastic and letting it bake for 6 weeks). But that's not practical where you are since your growing season is so short and your sun is too weak outside the growing season to bake the soil.
But for the most part, if you get some freezing weather in the winter the soil-borne fungi are killed off by the cold. So after you move your raised beds, you can probably sanitize the soil just by tilling it up and leaving it in standing rows so that the cold weather can freeze the pathogens in the soil more easily.
