Re: New to canning - Do I really need a pressure cooker?
The upside down trick will seal jars but it doesn't kill any bacteria in the jars. You really should process jars in boiling water for safety. Most of the time you'll be fine but why risk botulism for 10-20 minutes time savings? Here is a news article on the topic:
Always use a recipe designed for canning. Check out the Ball website or get the Ball Blue Book. In general fruits, jams and pickles can be canned in a boiling water bath. Veggies need to be done in a pressure canner. Depending on the recipe tomatoes can be done either way. I use my pressure canner because I have it handy but there are recipes that are safe for boiling water.
Kristie mom to two girls, ages 5 and 8, and two boys ages 3 and almost 1!