Preserving Tomatoes in Canada

September is the single biggest preserving month in Canada, and tomatoes are why. A bumper crop comes in faster than anyone can eat it, and there are four good ways to put it up: water-bath canning, freezing, and drying all earn a place depending on how much freezer and shelf space you have.

One rule governs all the canning here: tomatoes sit right on the pH 4.6 line, and modern low-acid varieties can cross it. Every tested canning recipe adds bottled lemon juice or citric acid to guarantee a safe acidity — bottled, not fresh, because fresh lemons vary too much to rely on. Skip that step and you've made a low-acid food that needs a pressure canner. The same logic is why you can't safely water-bath a meat-and-onion spaghetti sauce.

Not sure which form to make? Whole vs crushed vs diced walks through which suits which winter meal. And if you've seen white sediment settle in the jar, that one explains when it's harmless and when it isn't. Every recipe cites Bernardin or Health Canada and points you at your altitude band.