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A Quick Canning Method for Preserving Tomatoes

Use this simple technique to ensure you can enjoy that tomato goodness months later

Produced by Danielle Sherry, Sarah Breckenridge, and Robyn Doyon-Aitken. Videography by Gary Junken. Edited by Cari Delahanty

Welcome to Homegrown/Homemade, a video series from We’ll be following a gardener (Fine Gardening executive editor Danielle Sherry) and a cook (Sarah Breckenridge) as they plant, maintain, harvest, store, and prepare garden vegetables. If you’re new to vegetable gardening, you’ll find these videos very helpful. In this video, the topic is tomatoes.

Episode 5: How to Preserve Tomatoes—Fresh Tomato Purée

Traditionally, canning tomato sauce is a lengthy affair, but you can speed matters considerably by making and canning a fresh tomato puree, which later on can be transformed into sauce, soup, or even ketchup. Wash, core, and chop 8 pounds of paste tomatoes. Cook them over medium heat until soft, about 10 minutes. Next, puree them using a tomato press or a food mill; this removes the seed and the skins. Now boil some water and get your canning equipment ready. You’ll need four clean pint Mason jars and lids. Put the lids into the boiling water to soften the rubber flanges. Meanwhile, take the tomato purée and bring to a boil.

When all is ready, put 1/4 teaspoon of citric acid into the bottom of each jar to prevent botulism, and fill the jar with purée, leaving 1 inch of head space. Stir with a rod to remove any air bubbles, wipe the rims, apply the flat lids and then the top bands that hold the lids in place. As the liquid cools, the lids will form a seal. Then put the jars into a rack, and process in boiling water for 40 minutes. Let them cool in the pot for 5 minutes, then transfer to a rack or towel, and let cool for at least eight hours. Properly sealed jars of tomato purée will keep up to a year in the pantry.

Episode 1: How to Plant Tomatoes

Here, Danielle shows Sarah a couple of tips for setting tomato seedlings in the ground. For the strongest plants, clip off the lower leaves first, then plant the stems deep in the soil. That allows roots to form along the underground portion of the stems, increasing the nutrient flow to the plant and anchoring it more firmly. Once the raised bed is planted, Sarah and Danielle set up stakes and netting trellises. It’s best to do this before the plants, and their root systems, start to grow.

Episode 2: How to Prune Tomato Plants

The weather has been warm, and the tomato patch has turned into a jungle, so much so that the bed is getting crowded. Pruning will make it manageable again, and also allow sun to reach the ripening fruit. The first order of business is trimming back any low-lying branches that touch the ground, followed by pinching out small suckers that appear below the first flower cluster. (A sucker is a shoot that angles out between the stem and the horizontal branches.) Larger suckers can be controlled by Missouri pruning, which involves snipping off the top of the sucker. Missouri pruning must be repeated from time to time.

As you prune, keep an eye out for dead, damaged and diseased leaves. These should be removed as well.

Mostly, it’s the indeterminate tomato plants that require pruning. Determinate plants need little pruning.

Episode 3: How to Train Tomato Plants

This year, the weather has been hot and dry, and Sarah’s tomato patch is a jumble of thriving plants. A combination of selective pruning and tying will restore order to the patch. Panty hose makes good tie material because it stretches. A figure-eight loop wrapped loosely around the stake and tied in a knot can be used to support stems as well as branches with fruit. (You can use strips of other fabric as well.) If you see brown spots forming on the fruit, they might be blossom end rot, a sign of inconsistent watering.

Episode 4: How to Harvest Tomatoes

It isn’t hard to harvest tomatoes, but the tricky part is determining when they are at peak ripeness. Danielle shows Sarah three things to check for: color, smell, and “squishability.” Red, yellow, and orange tomatoes should be bright red, yellow, and orange, respectively; pink-fruited varieties should be a dusty rose color. Green varieties such as Green Zebra should be mostly green, with just a little yellow. Black tomatoes such as Black Krim should have a dusky purple color. Next, check aroma. The tomato should smell like a ripe tomato. As for squishability, pressing a ripe fruit with your finger should make an indentation that springs back. If the fruit is hard, let it ripen a while longer. If the indentation stays, the fruit is overripe.

As fruit ripens, the bottom leaves of the plants may turn yellow and brown. That’s normal; no need to worry.

Previous: How to Harvest Tomatoes Next: Learn to Can Tomatoes, Step by Step
View Comments


  1. shasta21 09/12/2014

    You are recommending only cooking these tomatoes 10 minutes FOR A PUREE? Did you mean "for a sauce"? A puree is thicker and needs a MUCH LONGER SIMMERING TIME to reduce and thicken up. Please revisit your instructions.

  2. susan749 09/30/2014

    A much easier way to do this is to use a food strainer (Victorio and Back to Basics both make good models) to which you simply halve or quarter tomatoes (no coring or chopping) without cooking them first. Then cook the puree in a large pan following the recipe in the Ball Canning book and can it.

  3. User avater
    LauraWilliams 01/15/2019

    It's awesome!!

  4. User avater
    DeweyMessier 01/16/2019

    Thank you!

  5. User avater
    BenjaminShaw 01/17/2019


  6. User avater
    DanielTaylorr 02/02/2019

    Nice idea!

  7. User avater
    Henry_Taylor 01/08/2021

    I swear my grandma would love it, thank you!

  8. user-7404617 09/08/2021

    Very helpful for canning - thank you!
    We've tried many methods, including the one suggested here with a food mill over the years, and have found one that works great for us; less messy, healthier, easier, and more space efficient:
    1. Core the tomatoes, seed them into the sink (just pull apart and scrape out the seeds and juice)
    2. Tear or quarter them into a pan. Simmer, then ladle out the excess water as they simmer.
    3. When the sauce or puree is at the desired consistency, just use an immersion blender to blend the sauce/puree together
    4. Can or freeze as desired.
    This method is much more space efficient, as it's thicker. Also healthier, as you retain the skins (but they get blended in once they're soft so you'll never know!). And much less messy and one less step not using a clunky food mill.

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