I've never canned before, but I'm gearing up to do it next year. I plan to focus on tomatoes to start with, though I'll try a few other things too. To oversimplify the question, if I want to put up 50 quarts of tomato sauce for the year, how many tomato plants do I need to plant? I know it's oversimplified, because it depends on the variety of tomato and how well the crop does and so on. But I gotta start somewhere I really don't know, 10 plants, 100 plants... ? A ballpark?