How to Can Tomatoes


These whole peeled tomatoes are what most people think of as canned tomatoes. They are quickly blanched in hot water, peeled, stuffed into jars, covered, and boiled to seal the jars. There’s no point in sugar-coating it: The process takes some time and is a bit of a hassle. However, it doesn’t require any special skills. Anyone with an excess of ripe tomatoes and the appropriate canning equipment can do it, and whole tomatoes are a perfect introduction to canning.


The tomatoes don’t need to be boiled more than a minute before being peeled and going into the jars, so there’s no real precooking involved. Salt is not required for this canned tomato recipe, although it can be added for taste if you like. And lemon juice helps keep the canned tomatoes from spoiling, so don’t skip it.


Canning whole tomatoes ingredients and tools

Bring a large pot or canning kettle full of water to a boil. As the water comes to a boil (which will take a while), use a sharp knife to cut a small “X” in the bottom of each tomato.


Cut an “X” into bottoms of the tomatoes

Prepare a large bowl of ice water and set it near the pot. Once the water is boiling, add the tomatoes. Cook them for about a minute, then lift them out with a slotted spoon and transfer them directly into the ice water so they can cool quickly.


As soon as the tomatoes have cooled off enough so that you can handle them easily, use a sharp paring knife to remove the tomato skins. After blanching, the skins should slip right off without too much fuss.


Remove tomato skins

Gather 6 quart-size jars (with rings and new sealable lids). Bring the water back to a boil, put the jars in the canning rack, and boil the empty jars for 10 minutes to sterilize them. Remove the jars from the water (empty any water back into the pot and bring to a simmer). Put the lids in separately, also for 10 minutes, to soften the sealant. Put a tea kettle full of water on to boil.


While the water is boiling, put 2 tablespoons bottled lemon juice in each jar. Stuff the jars evenly with the tomatoes. If you don’t care how “whole” they are in the end, really cram them in there, releasing the juices from some to create enough liquid to cover them. Cover the tomatoes with boiling water from the tea kettle, if needed, leaving 1/2 inch of headspace at the top of the jars.


Place tomatoes in jars with water

After wiping the edges of the jars clean, place the lids and rims on the jars, set the jars in the canning rack, and lower them into the boiling water in the canning kettle or other large pot. The jars should be completely submerged and covered by 1 inch of water. Cook, with the water boiling the whole time, for 45 minutes, adding more hot water as necessary to maintain the water level.


Remove cans from their water bath and set them on a counter to dry and cool. Do not disturb them for 12 to 24 hours. Check that the jars have properly sealed and store them in a cool, dark place until ready to use.

While you can leave the skin on tomatoes when canning, they can be tough and a bit bitter. You’ll notice that commercially canned tomatoes are peeled for this reason. If the skin doesn’t bother you, leave it on. Otherwise, quickly blanch the tomatoes and peel them before canning for a more pleasant experience.

Is Adjusting for Altitude Really That Important?

To ensure the canned tomatoes are safe for long-term storage, you need to adjust for altitude. For water bath canning, the canning time needs to be extended if you live higher than 1,000 feet above sea level. While altitude is often associated with mountainous regions, it can affect those who live in seemingly flat areas. In the U.S., check with your local county extension office for accurate elevation information and other canning tips.