Fall is almost here and gardeners may still have tomatoes to harvest. But once a frost or freeze occurs, those tomatoes should not be used for canning.
When tomato vines die, the acid level changes resulting in less acidic tomatoes. Even if recommended canning methods are used, these tomatoes will still be unsafe. The tomatoes can still be eaten fresh or frozen for later use.
Green tomatoes can be canned as a relish, salsa, or as regular tomatoes. Learn more at www.ksre.ksu.edu/bookstore/pubs/MF1185.PDF.