Whole cherry tomatoes are not covered by a tested home-canning process. Ohio State University Extension and Illinois Extension both advise against canning them whole, and the National Center for Home Food Preservation (NCHFP) publishes processes only for whole or halved tomatoes in general, not for cherry or grape types. Freezing is the method extension sources point to when the goal is whole fruit. If you still adapt the standard whole-tomato process, every jar has to be acidified, the fruit should be peeled, and the processing time has to match the pack you actually used.
Why there is no approved method for canning cherry tomatoes whole
USDA and university canning times come from lab tests of a specific preparation: fruit size, peel or no peel, how tightly the jar is packed, how much liquid is added, and how long heat takes to reach the coldest point in the jar. Cherry and grape tomatoes were never run through that testing.
Ohio State asked Elizabeth Andress, then director of the NCHFP, about the gap. Her answer, reported by the university, was that the tests simply have not been done, that neither she nor OSU Extension specialists recommend canning whole cherry tomatoes, and that someone who insists on trying it would have to use the process written for tomato halves — with no promise of a good result. Illinois Extension states the same limit more briefly: cherry and grape tomatoes are not recommended for canning.
Size is the practical problem. Small fruit packs tighter than halved slicing tomatoes. A denser pack slows heat penetration, which is the same reason USDA does not recommend home-canning diced tomatoes. Commercial canneries use different equipment and controls, so a jar of diced or cherry tomatoes on a grocery shelf is not evidence that the same pack is safe in a home canner.
Cherry tomatoes can still go into tested tomato sauce, crushed tomatoes, or juice, once they are prepared the way those recipes require. The restriction is on canning them whole.
What every tomato canning process requires
Tomatoes sit on the line between acid and low-acid foods. Measured pH often falls between about 4.0 and 4.6, and some fruit, including overripe tomatoes and fruit from dead or frost-killed vines, can land above 4.6. Clostridium botulinum, the bacterium that produces botulinum toxin, can grow in a sealed jar when the pH is above 4.6 and the food was not pressure-processed long enough to destroy its spores.
Because variety, ripeness, and growing conditions all move the pH, USDA and the NCHFP require added acid in every jar of whole, crushed, or juiced tomatoes. That rule applies to boiling-water processing and to pressure canning. The short pressure processes used for tomatoes were developed on acidified fruit.
Add one of these directly to each jar before filling:
- Bottled lemon juice: 1 tablespoon per pint, 2 tablespoons per quart
- Citric acid: 1/4 teaspoon per pint, 1/2 teaspoon per quart
- Vinegar of 5 percent acidity: 2 tablespoons per pint, 4 tablespoons per quart
Use bottled lemon juice, not fresh-squeezed. Bottled juice is standardized; fruit from a tree is not. Bottled lime juice is an accepted substitute for bottled lemon juice. Citric acid changes flavor the least. Vinegar is safe at those amounts and is the one most people taste. Up to 1 tablespoon of sugar per quart may be added to soften the acid note. Salt is optional — 1/2 teaspoon per pint or 1 teaspoon per quart — and does not make the jar safe.
Do not can tomatoes from dead or frost-killed vines, or fruit that is soft, cracked, moldy, or badly overripe. Disease-free, firm, vine-ripened fruit is the standard. Underripe fruit is more acidic than ripe fruit and may be canned under the same tested directions, but it will not taste like ripe cherry tomatoes.
Older methods are not substitutes. Open-kettle canning, oven canning, and dishwasher canning are not accepted processes. Oil does not belong in the jar: it can shield bacteria and can damage lid gaskets.
If you adapt the whole-tomato process anyway
This is the NCHFP method for whole or halved tomatoes packed in water, which is the process Andress pointed to. It is not a cherry-tomato endorsement. Treat it as the closest tested procedure, and expect quality losses described later.
An average of 21 pounds fills a canner load of 7 quarts, and about 13 pounds fills 9 pints, using ordinary tomatoes. Cherry tomatoes are lighter per piece, so weigh rather than count.
Wash the fruit. Dip it in boiling water until the skins split, then move it to cold water and slip the skins off. Standard directions say 30 to 60 seconds; small fruit often splits sooner, so watch the skins rather than the clock. Remove stems and any cores or blemishes. Tested tomato processes were built on peeled fruit. Leaving skins on can toughen the finished tomatoes, add bitterness, and change how heat moves through the jar, because that variable was not part of the original tests.
Add the acid to the empty hot jar first so none is forgotten. Pack peeled tomatoes with 1/2 inch of headspace.
Raw pack: fill with raw peeled tomatoes and cover with boiling water, still at 1/2 inch headspace.
Hot pack: cover peeled tomatoes with water, boil gently for 5 minutes, then pack hot fruit and cooking liquid at 1/2 inch headspace. Hot pack drives off some air and usually floats less.
Slide a bubble tool or non-metal spatula around the inside of the jar, adjust headspace, wipe the rim, and apply a lid and band fingertip-tight. Jars in a boiling-water canner need 1 to 2 inches of water over the lids. Start timing only when the water is at a full rolling boil. At the end of the time, turn off the heat and wait 5 minutes before lifting the jars. Cool them upright and undisturbed for 12 to 24 hours, then check the seals.
Boiling-water times for water-packed whole or halved tomatoes, hot or raw pack:
- Pints: 40 minutes at 0–1,000 feet; 45 minutes at 1,001–3,000 feet; 50 minutes at 3,001–6,000 feet; 55 minutes above 6,000 feet
- Quarts: 45, 50, 55, and 60 minutes at those same elevation bands
Pressure canning is allowed for this same pack, and the jars still get acid. Dial-gauge options are 10 minutes at 11 pounds (0–2,000 feet), 12 pounds (2,001–4,000), 13 pounds (4,001–6,000), or 14 pounds (6,001–8,000), or 15 minutes at 6, 7, 8, or 9 pounds across those same bands. Weighted-gauge options are 10 minutes at 10 pounds up to 1,000 feet and 15 pounds above that, or 15 minutes at 5 pounds up to 1,000 feet and 10 pounds above that. Follow the gauge and elevation you actually have. Do not shorten the time because the tomatoes are small.
A raw pack with no added liquid is a different process: press peeled tomatoes until juice fills the gaps, leave 1/2 inch headspace, and process pints or quarts for 85 minutes in boiling water at 0–1,000 feet, adding 5 minutes for each higher elevation band used in the water-pack table. That long time is hard on cherry tomatoes.
Do not add garlic, onion, peppers, oil, flour, or cornstarch. Those change acidity or thickness and are outside the tested pack. A tested salsa or sauce recipe is the place for those ingredients, in the amounts that recipe lists.
Quality problems that show up with whole cherry tomatoes
Even a correctly processed jar often looks worse than fresh fruit.
Floating is common with whole tomatoes, especially raw pack. Air inside the fruit escapes during processing and the pieces rise. A sealed, properly processed jar is not unsafe because of float. Hot pack, a firm pack, and bubble removal reduce it. Turning cooled jars does not fix the cause.
Skins left on usually separate into tough curls. Peeled cherry tomatoes are fiddly, and the short blanch can soften them before they ever see the canner. After 40 or 45 minutes at a boil, many collapse. The jar is then closer to tomatoes in their own juice than to whole fruit you would toss on a salad.
Seeds and gel make a watery pack. Water-packed tomatoes taste thinner than fruit packed in tomato juice; the juice pack is another tested NCHFP option and uses the longer process times published for that style, not the water-pack times.
Siphoning — liquid lost during processing — usually comes from a too-full jar, trapped air, or a sudden pressure drop. As long as the seal is good and the tomatoes stayed covered enough to process evenly, it is a quality issue. A jar that never sealed should be refrigerated and used soon, or reprocessed with a new lid within 24 hours using the full original time.
Before opening any home-canned jar, check for a broken seal, spurting liquid, rising bubbles, mold, or an off smell. Those are discard signs. Botulinum toxin cannot be seen or tasted, which is why the process has to be right before the jar is stored, not judged afterward.
Better ways to keep cherry tomatoes
Freezing matches the way most people want to use this fruit. Wash and dry firm tomatoes, freeze them in a single layer, then bag them. Skins do not have to come off. Frozen whole tomatoes hold for sauces, roasting, and soups; the texture will not return to fresh, so they are a poor swap for raw salad tomatoes. No acid is required for freezing.
Drying works if you want a shelf-stable pantry item without a canner. Halve the tomatoes, dry until leathery and no longer sticky, and condition them in a jar for several days to even out moisture before long storage. A dehydrator or a low oven both work; time depends on size and humidity. Dried halves rehydrate in pasta, grain salads, and oil only after drying — do not pack fresh tomatoes in oil and leave them at room temperature.
Sauce, crushed tomatoes, and juice are the canning routes that already have tested directions. Sort soft cherry tomatoes into those batches. Peel as the recipe directs, acidify every jar, and use the time published for that product. Crushed tomatoes are hot-pack only. Do not invent a hybrid of whole cherry tomatoes and a sauce time.
A large cherry-tomato crop is also a reason to roast and freeze rather than can. Roast until they collapse, cool, and pack in freezer containers. That keeps the concentrated flavor without a density question in the jar.
Questions people ask after the main answer
Can grape tomatoes be canned whole if cherry tomatoes cannot? No. Extension guidance names both. Grape tomatoes are smaller and denser, so the heat-penetration concern is at least as large.
Does pressure canning remove the need for lemon juice? No. Acid is required for the tested tomato pressure processes as well as for boiling-water processing. Pressure shortens the time; it does not replace the acid step.
Is a jar safe if the tomatoes floated or the liquid separated? Float and separation are quality defects when the seal is sound and the full tested process was used. They are not, by themselves, signs of botulism. A failed seal, mold, or off odor is a different matter: discard that jar.
Can skins stay on to save time? Tested whole-tomato directions say to peel. Processing times assume peeled fruit. Skins also toughen and can taste bitter after canning. For freezing or drying, peeling is optional.
How long do sealed jars keep? A sound seal and cool, dark, dry storage protect safety. Quality is best within about a year. After that, flavor and texture decline even if the seal holds.