How to Can Tomatoes

Safely Canning High-Acid Tomatoes

Jul 23, 2018


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By canning tomatoes, you can enjoy that garden-fresh tomato taste in sauces, soups and stews all year long! Here’s how to can tomatoes, step-by-step.

First, when it comes to canning tomatoes for the rest of the year, I like to let my tomatoes get super-ripe on the vine. Farmers really don’t have this luxury, as the fruit becomes too easy to bruise at this stage. However, tomatoes will continue to ripen in the box or on the counter, so it’s best to purchase your canning tomatoes a few days in advance of the processing.

I also like to incorporate other flavors with my tomatoes because it is only in the summer that I have access to fresh basil, oregano, thyme, and garlic.

A Word of Warning

Canning is a great way to preserve your harvest, but it must be done correctly. Improper canning techniques can lead to the growth of the bacteria that causes botulism—a potentially deadly illness. It’s very important that you only use water-bath canning on high-acid foods (high acidity kills the dangerous bacteria). Low-acid foods must be canned in a pressure canner or must have an acid, such as lemon juice or vinegar, added to the cans.

Tomatoes can be either high-acid or low-acid depending on variety. In this article, the author uses home-grown, high-acid tomatoes, which is why the water bath method is used and no supplemental acids are added.

Warning: If you do not know the acidity level of your tomatoes, DO NOT use the water bath method. It is unsafe. Instead, use Pressure Canning.

Canning Supplies for Canning Tomatoes

  • Super-ripe tomatoes, fresh herbs, extra-virgin olive oil, onions, red peppers, salt
  • Heavy cooking pot with boiling water, pan of cold water
  • Slotted spoon
  • Knife and cutting board
  • Small chopper or food processor for garlic
  • Canning jars and lids (as many as needed), screw band, cloth to wipe the jars, jar tongs
  • Funnel and ladle
  • Marker to label cans

Preparation for Canning Tomatoes

I place some extra-virgin (organic) olive oil to thoroughly cover the bottom of a heavy cooking pot. I then take a few onions and a red pepper and cut them into smallish pieces and drop them into the pot. Adding a dash of salt, I let these cook until they are soft.

While the onions and pepper are cooking, I set a pot of water to boil as I wash the tomatoes. Then, using a slotted spoon, I dip the tomatoes (maybe three or four at a time) into the boiling water until the skins slip or about 30 seconds. Removing them with the spoon, they immediately go into a pan of cold water. They are then placed on a clean countertop while I do the rest of them. Once all the skins are loose, I cut out the stem and tough part of the inside and pull off the skin. Placing the tomato on a cutting board, it gets cut into small pieces.

This, of course, is the “proper” way to cut up the tomatoes, but I often do the “Lucy” (more fun) version. Making sure that I have clean hands, I stand above the compost bucket, pull off the skins and mush the tomatoes into the pot with my hands and through my fingers (reserving the stem and tough interior). This tactile experience is quite exhilarating.

Stirring frequently, I slowly add all of the tomatoes to the pot. I then wash several bunches of basil, oregano and thyme and peel quite a few cloves of garlic. Using a garlic press, a small chopper or a food processor, the garlic gets diced into very small pieces and added to the mix. The other spices then get torn into small pieces and also tossed into the pot. The mix is now ready to cook for about an hour in order for all of the flavors to blend together.

It’s important to be sure that this blend remains mostly tomatoes. We want the mix to be acidic in order to be able to preserve it properly. Also—stay away from low-acid tomatoes (a few are fine, but not too many).

How to Can Tomatoes

Wash the canning jars and lids and place aside. Jars get used year after year, but lids can only be utilized once. Fill a canner ¾ full of water and set on the stove to boil. Line up the jars and put 1 teaspoon salt in the quarts or ½ teaspoon of salt in the pints (salt, like sugar, is a preservative).

Once the water is boiling, we are ready to continue. I use a funnel over the top of the jar when I ladle my special mixture into it. Be sure to leave 1 inch of head space at the top. Next comes a VERY IMPORTANT step—it’s absolutely critical to wipe off the top of the jar with a cloth before putting on the lid. Any tiny particle of food left on the rim will cause a jar to not properly seal. Pop on the lid, adjust the screw band (tightly) and place in the water bath with jar “tongs”.

Make sure that everything continues in a soft boil and that there is at least 1 inch of boiling water above the top of the jars. Put the cover on the pot and start timing the processing; 40 minutes for pints and 45 minutes for quarts. A small battery timer is handy for this. After cleaning up the accrued dishes, I take a break and read while my jars are dancing away.

Once the timer dings, I turn off the stove and very carefully take the top off of the pot so that the steam goes away from me. With a nice trivet on the table or counter nearby, I slowly take out each jar (again with the “tongs”) and place it to cool. Be sure that the trivet is not located in a draft as a cold breeze can crack the jars at this point. This is also why I move them slowly.

Once all of this has been accomplished, I generally call it a day. There will be a noticeable (and reassuring) “pop” as the individual jars seal. I look lovingly at my beautiful trivet of summertime bounty and I wait until the next day to finish the job.

The jars are cool by morning. I take off the screw bands (carefully) because they sometimes get food on them and leaving them on makes them rust. They get washed and put aside for next year. I label each and every lid (this way you won’t have to scrub any labels off of the jar because the lid gets tossed anyway) with the year and the contents. Into the pantry go the canned tomatoes to await use in canned tomato soup, stews, American chop suey (I cook the elbows right in the mix) or anything else I decide to make during the long winter months. Yum!

If you need more advice on how to can your vegetables, or are looking to can more than just tomatoes, try our vegetable canning guide. If you feel that you’d rather dry your tomatoes than can them, learn how here. Whatever you choose, good luck making the most of your tomato harvest!

About This Blog

Celeste Longacre has been growing virtually all of her family’s vegetables for the entire year for over 30 years. She cans, she freezes, she dries, she ferments & she root cellars. She also has chickens. Celeste has also enjoyed a longtime relationship with The Old Farmer’s Almanac as their astrologer and gardens by the Moon. Her new book, “Celeste’s Garden Delights,” is now available! Celeste Longacre does a lot of teaching out of her home and garden in the summer. Visit her web site at for details.

Reader Comments

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're-canning old tomatoes

I have many quarts of tomatoes left from the last few years of canning. Can I open them, boil the contents,and re-can them so they have a longer shelf life?


Hi Cindy, I’m not sure that you can re-can tomatoes that have already lived in jars for years. I think that they are good for more than one year canned, though. I always take last year’s and put them in front of this year’s. That way I eat them first.

Tomatoes 1

I have been reading a lot of comments and am totally confused.
I just canned 18 quarts of tomatoes with only canning salt. Was I supposed to use lemon juice also? I used canning tomatoes from my local farm. I will be doing up ROMAS next. But before I do I want to make sure I know how to do them up right.
I did all using hot water bath.

Adding Lemon Juice

It’s always better to be safe than sorry, so yes, we would recommend adding 2 tbsp of lemon juice per quart in order to bring the acidity to safe levels. Assuming you only recently canned the tomatoes, you should unseal them, add the 2 tbsp of lemon juice, then seal them again in a water bath. Use lemon juice with the romas as well. You can use bottled lemon juice found in your local grocery store.

Tomatoes ll

If I did all 18 quarts wrong can I start over with what I have or are they garbage?

Slow cooker

I do not have a large pot. Can a slow cooker be used or just use the pot and it will just take longer to get them done?


How much pickling salt would I use for 53 lbs of tomatoes


I couldn’t tell you how much salt to use for that poundage. I put the salt in the jars before I add the tomatoes. I add 1/2 teaspoon for pints and 1 teaspoon for quarts.

salt used in canning

I was always told to use PLAIN salt or canning salt when canning. No iodized salt!!! When I can my tomatoes I use a teaspoon of plain salt and a tablespoon of lemon juice in the bottom of each quart jar. (That way I don't forget to put anything in!! I put the dry in first and lemon juice next.) I would think that if I used the pressure canner, I could omit the lemon juice?

pressure canner

Hi Pamela, I used to use my pressure canner all the time. However, Sally Fallon Morrell from the Weston A. Price Foundation says that it’s not good to pressure cook food. It isn’t as bad as a microwave, but it does change the nature of the food. I don’t use mine anymore.


I did 5 quarts and forgot the salt! Is there a time frame to use them by?

time frame

Hi Gaylene, I don’t know exactly what the time frame would be, but I would think that it would be best to use them soon.

canning tomotoe sauce and juice

I am first time caner and I didn't add salt or lemon juice. What should I do? Should I redo the canning process again? What do you mean by using them soon. How long? I have 18 jars of sauce done. Did it about 2 weeks ago. Please help me. Just worried about the 18 jars of sauce.

I am now ready to do tomato juice-about 16 quart. I will add salt and lemon juice to this batch. Is that correct?

Could you please email me.

Linda Loewenhagen

Canning or freezing tomato sauce

I always add wine to my tomato sauce. Won’t this make them just as acidic as lemon juice. It will certainly taste better!

Some wines are more acidic

Some wines are more acidic than others. I don’t actually know if any are as acidic as lemon juice.

Acid added

I use citric acid powder sold by Ball. raises the acid level but does not change the taste of the tomatoes.

Jar size

Ah...I see the options for both are here...thank you :)

Canning jar sizes

What size canning jar is this for? I'd like to use a quart (1.5l) jar....can I do that with this recipe? Thank you!

Canning tomatoes

Hello I am canning tomatoes and have for yrs and I blanch the tomatoes then cut them up cold pack them and only put canning salt on top and pressure cook them..So my neighbor told me that I HAVE to put lemon juice in them or they will not be good...But I have been doing the same thing for yrs and never have gottem sick....I will start to put the juice in from now on but they should be ok right. I did 29 quarts and 11 pints...Don't really want to through all that goodness out..Just would like your comment..Thank you

canning tomatoes

In future, definitely put in the lemon juice to be on the safe side. Tomatoes vary in acidity, depending on variety, ripeness, etc.

Hi Kris, I don’t use any

Hi Kris, I don’t use any lemon juice. If it’s botulism that you are worried about, this organism expands what it affects. That’s why you never eat canned food that is bulging. Since I remove the screw bands, the lid would be loose. I would never eat food that had a loose top for any reason.

Canning tomatoes

Your instructions are the most thorough I've found. Thank you for that. I'd like to add a few things I've learned. Before filling them, clean jars can be heated in the oven at 200 degrees F and then removed and filled with hot tomatoes, preventing thermal shock. Also, after the boiling of the filled jars is complete, sometimes the lids will pop as you remove them from the canning pot. This is normal. Always check the lids after the jars are cooled.

Canning Tomatoes

I've been canning tomatoes for over 30 years, Italian style. I grind the tomatoes after cooking, jar the sauce, and then boil The only ingredients I add, after grinding, are fresh basil leaves and a pinch of salt on the top of each jar. I learned from two Old-World Italians. One of them would re-cook after grinding, but did not boil the filled jars. The other would fill the jars with the ground tomatoes and then boil the jars. In 20 years of using the second method, I've only had to dispose of 3 jars (a bad tomato crop). The first method resulted in more waste. Believe it or not, the "pinch of salt" is a preservative. Adding garlic, onions, or peppers to the sauce before jarring may result in more waste -- more prone to bacteria forming.

Pressure canner

In a canning class that I took it was recommended that we use a pressure canner for tomatoes was the tomatoes don't have as much acid as they used to. Take the canner to 15lbs then turn off the heat. I do live in Georgetown, Colorado elevation 8500 ft.


do you leave the seeds in the sauce? I spend a lot of time trying to remove the seeds

Hi Holly, If I only have a

Hi Holly, If I only have a few tomatoes, I leave the seeds in the sauce. If I have a lot of tomatoes, I put them through my squeezo-straino (a machine that sends the seeds and skins out one side and the pulp out another). The machine takes time to clean but saves time if there are quite a few tomatoes. I don’t mind sauce with the seeds, but some people do.

Better methods for canning tomatoes

When using a water-bath process, you MUST add acid to tomatoes. The National Center for Food Preservation has very complete instructions for pressure canning and water bath canning for whole, crushed, sauced, and juiced tomatoes.

Hi Rebecca, If it makes you

Hi Rebecca, If it makes you feel more comfortable, you certainly can add acid to tomatoes. However, I have been canning tomatoes for almost 40 years and have never had a problem not doing so. I do, however, use tomatoes that are NOT low acid.

I have been stewing tomatoes

I have been stewing tomatoes for over 30 yrs. I add 1/4 cup lemon juice to a dutch oven size pot. After I put the cooked tomatoes in the jars, I add 1 tsp or pickling salt and 1 tsp sugar and seal. That is all I do.
Never heard of a water bath until last week

Hi Chris, I have never

Hi Chris,

I have never heard of doing tomatoes this way. With jams, after sterilizing the jars and lids, they don't need to be processed because of all the sugar that will preserve them. I wouldn't recommend doing tomatoes this way.

boiling tomatoes

How do you boil them? In a big kettle and put into sterilizes them jars and wait til the

May I safely substitute brown

May I safely substitute brown sugar for granulated sugar when I can this tomato recipe? I will be using a pressure canner. Thanks

Hi Ruth, I don't use any

Hi Ruth,

I don't use any sugar when canning my tomatoes. You want to be careful to keep the mixture acidic when canning this way.

I usually pour some vinegar

I usually pour some vinegar in the water that the jars are set in.....eliminates the mineral deposits on the jars from the water...haven't canned for years....miss it....will have to start up again.

You can also just freeze the

You can also just freeze the mixture in freezer bags...I just smooth out excess air and lay them flat on a cookie sheet and set in freeze....they store very easy this way. That is if you have freezer room.

I have been canning

I have been canning tomatoes-stewed, plain & salsas

Can you can green peppers or

Can you can green peppers or jalapeno peppers using the water bath method? If so, are there any special additions needed, like salt or lemon juice?

Hi Bill, Peppers are not

Hi Bill,
Peppers are not acidic so you would have to be very careful canning them. It would need to be done in a pressure canner and only in small jars. Refer to Ball's Blue Book of preserving for complete instructions.

I have been canning

I have been canning tomatoes-stewed, plain & salsas. I have never processed my tomatoes. My mother and grandma never did. I bring all to a boil for 10-15 mins then can in boiled jars and lids. May have 11 jar out of approx 12 doz spoil. Am i just lucky? Been doing it this way for approx 38 yrs.

Hi Janet, I would not want

Hi Janet,

I would not want to trust tomatoes that hadn't been processed. You may just have been extremely lucky...

My mother in law taught me

My mother in law taught me how to process tomatoes. She did it the same way you describe. I've been canning for 34 years; hardly ever lose a jar.

Canning tomatoes

I just checked again with several members of my family who/their descendants have been canning tomatoes since jars were available here and/or in the homeland. None of them have ever used a water bath with the same success/loss rate as JHagerty. They all say the loss is due to residue on the rim. Just sayin'. AND, If you are just starting and want to use the water bath, go ahead as it won't change the product at all. Tomatoes jarred in glass are the best way to go.

to water bath or not

...and my comment above concerns tomatoes cooked into a sauce. We DO water bath tomatoes that are canned whole (and therefore not cooked & packed hot).

Hi Carol, I always water bath

Hi Carol, I always water bath (or steam bath) my canned sauce. I rarely, if ever, lose a jar, although I am sure to wipe the rim of the jar to avoid food stopping it from sealing. Since I have already cooked the sauce for hours, it really doesn’t change it much.

Truly an amazing article! I

Truly an amazing article! I have gardened
all my life, in the desert, in the mountains,
and in "the flat lands"! I thought my
gardening/canning days were over when I
moved to an aapartment. That very first week my sister gave me the greatest house warming presents! She gave me 5 of those crazy "Topsy Turvy" gardening bags that you hang on your patio or balcony! It's unbelievable just how many tomatoes are produced by growing a plant that way! I
actually have switched up a couple of them and grown peppers and even zucchini. Last year I even had to go out and buy 4 extra cases of jars, because I had that many extra tomatoes! When I can my stewed tomatoes or my mexican mix, I have never put any salt in the jars. From the time I
started canning, I had several family members that were on sodium restriction. I have never had any bad batches. Thanks again for the article! It's got me all excited for this years canning season!

Dear Desert

Dear Desert Dreaming,

Thanks for your kind words! I would be leary, though, of not adding any salt. I personally don't use table salt which is often restricted because it isn't good for us. I use either sea salt or Himalayan pink salt. Salt that doesn't possess some color usually has been processed and all the minerals taken out. Table salt also often contains dubious ingredients designed to make it pour better, but largely untested for health qualities.



Hi Harold, I would be leery

Hi Harold,

I would be leery of not processing the tomatoes. For safety sake, process in a water bath.

I love canning and welcome

I love canning and welcome your tips. I save the used lids and use canning jars all year long. When i'm not concerned with "sealing", I store rice, pasta, various dry goods and leftovers in the quart and half-gallon jars. I use the 1/2pt preserve jars to make lo-cal desserts. Pour 1/2 cup sugar free jello or pudding into clean jars. When set, top with a tbs of whipped topping, and garnish with a sprinkle of graham cracker crumbs and a sprig of mint. Place used lid and ring on jar. I now have a selection of desserts to choose from in convenient one serving containers.

Hi Marie, Thanks for those

Hi Marie,

Thanks for those tips!

What great ideas thank you

What great ideas thank you for sharing :)

I also used my jars when not

I also used my jars when not in use for drinking glasses....much strong than glasses from the store.

Can I safely freeze my

Can I safely freeze my tomato's to remove skin's and stems before canning, or must I blanch them?

Can I safely skip blanching

Can I safely skip blanching tomato's, by
freezing them instead? Freezing & using the "Lucy" method seems to be the quickest & easiest method to me, but is it safe?

Hi Just Little Ole Me, I've

Hi Just Little Ole Me,

I've never heard of the "Lucy" method. I don't see any reason why it shouldn't be safe since you are going to can them eventually, but, again, I don't know this method.

The "Lucy" method I was

The "Lucy" method I was refering to is from the above article. Using my hands to remove the stems & skins.
Thank you so much for the answer, you've saved me so much time!

I use my slow cooker to cook

I use my slow cooker to cook down large batches of tomatoes. It keeps the kitchen from being so hot in these Southern summers! Like you, I add garlic and fresh herbs from the garden, but I also grate onions, carrots and peppers and add to the mix sometimes. When I'm ready to can them, I add a tablespoon of fresh lemon juice to each quart jar. This makes an oh-so-good spaghetti sauce for cold winter nights

Do you use a regular stock

Do you use a regular stock pot or a pressure cooker?

Hi dfret, I definitely use a

Hi dfret,
I definitely use a regular stock pot. Food needs to be slow-cooked to maintain its integrity. I don't use pressure cookers or microwaves. The former just changes it some but the latter changes the actual structure of the food (in my opinion, turning it into a toxin).

It is correct that you take

It is correct that you take off the bands, but only after completely cooled off. If sealed properly the flat lids will not come off easily, but the rings will rust over time partly due to water getting under the rims while in the bath but can also be from food getting under the rims during application. Hope this helps, I was leary at first but they do stay just fine. Also like she said in the article, it saves you from having to purchase more rings next year if you wash, dry and store them properly, you'll only have to purchase more flat lids next time.

Great ideas: 'Eat what you

Great ideas: 'Eat what you can and can what you can't' ~

I like plain canned tomatoes,

I like plain canned tomatoes, but I like a few with bell peppers. Cold canned I think is what my Mom called it.

I love canning! What it

I love canning! What it saves on food bill is shocking over a year period. I have a garden I can from, so I know exactly what is going into my jars of yummy goodness. There is something so awesome after a day of canning, seeing a table filled with cooling jars of every color and popping lids. The next day boxing them up and putting them in the basement to store. As I use them up over the year I put the empty jars back in their box bottom up. I tied the tomatoes up today and I have so many baby tomatoes. I should be getting my first ripe ones by June 1st

Hi 4Beetender, I love

Hi 4Beetender,
I love canning, too. And, you are right, it is amazing how much you can save on your food bill. It's also fantastic to know what is in your own food.

Canning Tomatoes

You take off the screw bands before storing the jars? So they just have the small flat lid on top of the jar opening?

Did you get a comment /answer

Did you get a comment /answer to your I was wondering the same thing. I cant see taken the screw bands its confusing to me....

It's all based on vacuum

It's all based on vacuum sealing the lid on tightly.
When the jars are removed from the boiling water they start to cool and that causes what air is in the jars and the ingredients to contract.

The pop the writer refers to is the lid slightly collapsing inward from the pull of the vacuum, thus sealing the jar. In essence, the vacuum will keep the lid in place and the jar sealed so the screw bands are not really required.

When you leave the rings on

When you leave the rings on your processed jars during storage, you will never know if the vacuum seal is good because the ring keeps the lid (flat) pressed tightly against the rim. That's also why jars shouldn't be stacked on top of each other. Ring storage is super easy, and can even be a work of art. Get a length of ribbon or rope or wool, tie a wide mouth ring to one end. Now slide your rings over the top and that wide mouth ring will stop them from falling off. You can mix sizes on the same length because the wide mouth will always slip over a regular size, and the regular size willl always slide through a wide mouth ring. Find a nail to hang them from. Mine are hanging in a kitchen window :-)

I leave my bands on too.

I leave my bands on too. Just because my grandmother did. I feel safer anyway.... it would save money I suppose.

Hi blqt, Yes, I do take off

Hi blqt,
Yes, I do take off the screw bands. They can get food from the processing on them and they will rust eventually if you leave them on.

I also remove my bands in

I also remove my bands in case of spoilage...If the bands are left on the jars will reseal and you would never know if it spoiled or not..With the band removed any spoiled or jars that unsealed can't reseal and the contents will let you know it spoiled..

Canning tomatoes

Brilliant presentation. Easy to follow and the finished product looks lovely!!
Thanks for sharing

Hi Eswin, Thank-you so much

Hi Eswin,
Thank-you so much for your lovely comments. I truly appreciate them.

What a beautiful picture of the canned tomatoes

I just felt moved to comment, those red tomatoes in glass jars are so stunning, like jewels. The photography at this site is beautiful anyway, I love decompressing by looking at sunsets and gardens. Celeste Longacre is just the kind of writer I adore, love reading all the homey stuff.

Hi Sally, Thanks so much for

Hi Sally,
Thanks so much for your lovely comments!


This is pretty much what I do, with the exception of peeling the tomatoes every time. Sometimes I actually leave the skin on them (I grow my own tomatoes--don't know that I would trust store bought ones to be pesticide free) because they do contain nutrients as well, and I just like them. I make sure that I wash them really well, but other than that there's no difference. They add interesting texture to spaghetti sauce and salsa--which we eat a lot of in this Texas home! And you can always use a hand blender to puree it prior to actually using the finished product six months later. Oh, and with regard to the fresh herbs, try using cilantro instead of basil and adding some fresh jalapenos and/or other green chilis and a bit of lime juice instead. You'll have your own version of that famous store brand--only better!

Hi hepnr, More great ideas!

Hi hepnr,
More great ideas!


I'm inspired! Excellent instruction for some amazing canned tomatoes.

We add just TWO simple steps

We add just TWO simple steps - Place LARGE dark bath towel over counter and up the back splash - Sterilizing jars in Dishwasher is great - or two @ a time in Microwave 2 seconds will do the trick .. With towel in place there is no mess what-so-ever - just toss in washer after filling/watre bathing and cooling jars. Also put tomatoes up in HALF gallon jars - then come SNOW out side/ in Crock pot - make your own Chili sauce/ketchup/pasta sauces and all things tasty -

Dear Sir Taz, Great ideas!

Dear Sir Taz,
Great ideas!


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