Don’t want your tomatoes to go to waste after the summer season ends? Use this easy and straight-forward beginner’s guide to canning tomatoes to enjoy tomatoes from the garden year-round!
Fresh tomatoes are a favorite vegetable in the summer, from Caprese Salad to Homemade Pizza Sauce. They’re also one of the easiest plants to start when growing your own garden.
However, it only takes a few plants to suddenly become overrun with tomatoes. And when you’ve eaten your fill of Hearty Spaghetti Sauce and Tomato Basil Soup, what else can you possibly make with all those tomatoes?
The answer – canning tomatoes!
Beginner’s Guide to Canning Tomatoes
The idea of canning can sound scary, but it’s like riding a bike – once you get the hang of it, it’ll never be hard again!
Plus, this beginner’s guide will explain exactly what to do – step-by-step – so you can take advantage of garden harvest tomatoes in August, farmer’s market tomatoes, or even a good deal at the grocery store, all year long!
What You Need for Canning Tomatoes
- Canning Jars: You need jars specifically made for canning (Ball and Weck are good brands) in either a 16 oz pint size or a 32 oz quart size. I tend to find the best deal on canning jars at Walmart, but these on Amazon are a good deal too. You can, however, re-use canning jars. If someone gives you gifts in mason jars, keep them!
- Canning Lids: Canning lids come with canning jars when you buy them, but it’s best practice to use new lids every time you can.
- Canning Rings: Also known as screw bands, you can reuse canning rings from canning jars. Do a quick count and make sure you have one ring for each jar you plan to can with.
- Canning Pot: You need one pot big enough to cover your jars plus 2″ of water. If you chose pint jars, you could probably use the typical 5-quart pot that comes with most cooking sets. If you’re using quart jars, you’ll need a big stock pot or canning pot. Using racks in the pot is optional.
- Small Saucepan: A small one like this that comes in your cooking set will work. It’s to keep the lids warm while you prepare the tomatoes and jars.
- Sharp Knife: For cutting tomatoes, I love this one.
- Cutting board
- One cookie sheet OR another large pot: Some canners keep the jars warm in the oven on a cookie sheet; others keep them warm in a big pot of water. Choose whichever method suits you.
Optional Tools for Removing Skins
- Medium Pot (optional, for removing skins): if you want to remove the skin because it’s tough or doesn’t taste good, you’ll need this.
- A big bowl of ice water (for removing skins, optional)
For most canning projects, you’ll probably already have most of these supplies. Double check you have enough jars in good condition (no chips or cracks), enough lids, and that your pots aren’t being used in another recipe and you’re good to go!
Ingredients to Can Tomatoes
This tutorial is for making diced canned tomatoes using ONLY tomatoes. If you want to can tomatoes using onion, peppers, garlic, carrots, or celery, you’re essentially canning salsa and you should follow the appropriate process times.
- Lots of firm raw tomatoes. Fresh ripe tomatoes are best for this recipe as they provide the most flavor!
- Lemon juice. Bottled lemon juice is best for canning because the acidity level is consistent.
- Salt
Note: This is everything you need for the cold-pack method, which is canning food that hasn’t been cooked. You can follow this guide for the hot-packing method of canning tomatoes.
How to: Canning Tomatoes Tutorial
Step 1: PREP
Prep Your Pot(s). Fill your CANNING pot (either the stock pot or 5-quart pot) ⅔ full with water and bring it to a boil. This takes some time, so go ahead and start this first.
Optional, if Removing Skins: Fill the MEDIUM pot ⅔ full with water and bring to a boil. (See additional recipe notes for more on removing the skins from the tomatoes.)
Warm the Canning Jars. Jars must be the same temperature as the water you’re canning them in. If you’re using…
- Cookie Sheets: Preheat the oven to 250F. Place the empty jars on the cookie sheets and place them inside the oven.
- Large Pot: Fill the pot half full with water and place empty jars inside. Bring to a simmer.
Simmer. Fill the SMALL saucepan with a couple of inches of water and place the lids inside. Bring to a simmer on a back burner.
Optional, if Removing Skins: Fill a big bowl halfway with ice water to create an ice bath.
Catch-Up. At this point, you should have up to 4 pots on the stove:
- CANNING pot for water bath canning
- COOKIE SHEET in the oven with jars on top, or a second large pot of water for warming jars
- (optional) MEDIUM pot for de-skinning
- SMALL saucepan for lids
Step 2: INSTRUCTIONS TO REMOVE THE SKINS (OPTIONAL)
- Remove the stems from the tomatoes and cut a small “X” at the bottom of the tomato. Place as many tomatoes that will comfortably fit in the medium pot, leaving about 1″ of water covering them. Dip the tomatoes in the boiling water for 30 seconds (use a kitchen timer).
- Use a slotted spoon to remove the hot tomatoes from the hot water and place them directly into the bowl of ice water.
- Allow them to sit in the water until they are cool to the touch.
- When cool, remove the tomatoes from the cold water and set aside to remove the skins. Repeat this process for the remaining tomatoes.
- When all the tomatoes have been boiled and cooled, peel the skins off and set aside.
Step 3: DICING THE TOMATOES
- Using your knife, carefully cut the tomatoes (peeled or unpeeled) into small pieces. The actual size of the diced tomato is a matter of personal preference. I cut my tomatoes (1-2″ in diameter) into pieces that are ⅓″ – ½″ in size. Simply quarter tomatoes if they are on the smaller side. You can also slightly crush the tomatoes if desired.
- As you’re working through the tomatoes, set aside any scraps and juice. They’ll come in handy in a moment!
- Remember that this tutorial is for the cold-packing method, not the hot-pack method. You want your tomatoes to be uncooked and raw.
Step 4: JARRING TOMATOES
- When all your tomatoes are diced, pull out as many jars from the oven that will fit in your big pot (mine holds 6) and start filling them up with the tomato mixture! You want to pack tomatoes in the jars lightly but well. Shuffle the jar on the counter to help the tomatoes settle into the nooks and crannies. Leave about ½-inch headspace at the top of the jar for expansion.
- When your jars are filled, add lemon juice to each jar. Use 1 tablespoon for pint jars and 2 tablespoons for quart jars.
- Measure salt into each jar. Use ½ teaspoon for pint jars and 1 teaspoon for quart jars.
- Fill jars with liquid, leaving ½″ of room at the top. You can fill the jars with either water or tomato puree. Personally, I chose tomato puree because it enhances the flavor of the homemade canned diced tomatoes and lets me use up my tomato scraps. (See the next step.)
- If you choose tomato puree, toss all your tomato juice, scraps, and skins you’ve been saving into a blender and puree until super smooth. You can then press tomatoes through a sieve if you’d like (I usually don’t).
- As you fill the hot jars with puree (or water), slide a chopstick or butter knife around the inside edge of the jar to remove as many air bubbles as possible. Rotating the jar back and forth on the counter (in a half-circle motion) also helps. Make sure to wipe the rim if any moisture is on the lip.
Step 5: WATER BATH CANNING TOMATOES (How to Can Tomatoes Without a Canner)
- When the jars are filled, carefully remove the lid and ring from the small pot of simmering water. Place the lid on the can, then the ring on, securing just enough so the lid stays on and doesn’t fall off. You don’t want to overly tighten the ring at this point. My trick is to turn it until it catches (and I can’t pull it straight off) and then another quarter turn.
- Place the jars in the canning bath and let them boil submerged in water. Processing times depend on your added liquid: 45 minutes if you used water or 85 minutes if you used tomato puree. Set the timer and occasionally check the water level to ensure it can stay covered.
Note: This is for the water bath method at an altitude of 0-1000 feet above sea level. If your elevation is different or you are seeking a different canning method, use this guide from the National Center for Home Preservation.
Step 6: COOLING THE CANNED DICED TOMATOES
- When the timer goes off, carefully remove the cans from the water bath (this is when a canning kit with a jar lifter comes in handy) and set them aside on a towel to cool for 24 hours until they reach room temperature. You should hear some popping over the hours as the lids seal themselves.
- Check for a good seal by pushing down on the center of the lid. If it doesn’t bounce back, you’re good. If it does bounce back, repeat the water bath method in the next batch OR put unsealed jars in the refrigerator and include them in a meal in the next few days. You can also freeze the tomatoes if you don’t have any meal ideas for tomatoes in the next few days.
- When the first batch of canned tomatoes is cooling, check to ensure you have enough water in your pot, adding more water if necessary. Then start working on the second batch by repeating the same process again.
- When all the tomatoes have been canned, cooled, and sealed, put them away and congratulate yourself for a job well done!
Homemade Canned Diced Tomatoes FAQs
Should you remove the skins from your tomatoes?
1. It depends on a) your preference and b) the type of tomato you’re canning.
2. If you like smooth, skinless tomatoes, remove the skins. If you’re canning tomatoes with tough skins (in general, the bigger the tomato, the tougher the skin), then you might want to remove the skins.
3. Me? My tomatoes are only 1-2″ in diameter, and I don’t really care if there are skins in my sauce, so I kept the skins on.
Is canning tomatoes difficult?
Canning your own tomatoes is NOT difficult at all. Seriously. If you think it is, it’s your mind playing tricks on you. Push the little voice aside and listen to me: It looks hard, but it’s really not.
Can I speed up the process?
Yes! Working in batches makes this process go MUCH faster. That means taking the skin off all the tomatoes at the same time, then dicing all the tomatoes at the same time, then putting them in jars at the same time… catch my drift? This process works really well – just make sure you have enough bowls and containers to hold your tomatoes.
How long do you can tomatoes in a hot water bath?
Tomatoes need to process for 45 minutes if you use water, or 85 minutes if you use tomato puree.
Do you have to can tomatoes in a water bath?
No! You can use a pressure canner to can tomatoes. Using a water bath is easier for some because you don’t need any special equipment, like a pressure canner.
More Questions on Canning Tomatoes
Do you really need lemon juice when canning tomatoes?
Yes! Tomatoes are naturally high-acid foods, but the ph needs to reach a safe acidity point to kill bacteria when you can AND prevent bacteria, molds, and spoilage from forming as the tomatoes sit on your pantry shelf. Vinegar or adding a teaspoon of citric acid are not suitable substitutes.
Can I use bottled lemon juice?
Absolutely! The lemon juice is purely to produce a high level of citric acid in the jars to keep the tomatoes to preserve the tomatoes. Bottled lemon juice has a consistent level of acidity, so it actually works better than fresh!
How many cans do 1-2 pounds of tomatoes make?
If you only have 1-2 pounds of tomatoes, you might only be able to squeeze 1 can from this recipe, which is about half of one quart of tomatoes. That being said, you’re going to want a TON of tomatoes, aka several pounds, to make this home canning process worth it. Otherwise, going through the trouble of canning them might not benefit you. You’re probably better off just freezing them whole or eating them up.
Can I use this process for whole tomatoes?
Yes! You can use this same process for whole tomatoes or halved tomatoes. Stewed tomatoes, crushed tomatoes will require a slightly different process that I have not tested.
What kind of tomatoes should I use for this method?
I recommend using Roma tomatoes or other larger, fleshy tomatoes for this method. Roma tomatoes and other large tomatoes have a lot of flesh and very little juice and seeds, making them perfect for use in sauces.
Do I need a pressure canner for this canning method?
Nope! A pressure canner is not needed for this canned tomato recipe. This is great news for those who are scared by the gauges, weighted gauge, and or gauge pressure on pressure canners!
The high acidity of the tomatoes makes them like other fruits when canning. Low-acid foods, on the other hand, would require a pressure canner.
Canning Tomatoes
Canning your own tomatoes at home has never been easier! Now that you have all the steps you need to can tomatoes at home, you’ll never go back to purchasing store-bought cans of tomatoes again! Try out this home food preservation method, and let me know what you think!
More Tomato Recipes for Food Preservation
- Homemade Tomato Sauce
- 15 Minute Spaghetti Sauce
- How to Make Tomato Powder
- How to Freeze Tomato Paste
Michelle
What to do with leftover puree? I have about 3 1/2 cups!!
Tiffany
Oh goodness! Tomato soup (2 recipes on this site), pizza sauce, vodka sauce, condense into ketchup or even paste! You can add to veg soups (about 1 cup per batch).
Glen
Can I just use normal pickling jars as the ones u talk about are not available here?
Tiffany
I’m not sure what you mean by “normal pickling jars” Glen, but as long as they’re clean jars w/lids suitable for canning, you should be fine!
Charlotte
Rule of thumb growing up: We tried to can enough from one canning season to another. Ergo, one year storage. I know people who stored their longer but we never seemed to. We kept ours in the cellar (basement). Store the same as you would anything you purchase ;in a glass jar that doesn’t need to be refrigerated.
chrystal
can you tell me how long these will keep and proper storage methods
Tiffany
I had these in my pantry for several months.
Valerie
I recently found your post on Pinterest and am extremely happy. I had planned to plant quite a few tomato plants this year with the plans of making tomato and pizza sauce but hadn’t considered diced tomatoes, your recipee has given me confidence and I can’t wait until summer to try it out. Thank you 😋
Tiffany
You’re welcome Valerie – welcome to Crumbs!
Willene Hall
I do this and I add cut up onion because I have so many of them, about half tomato and half onion. When i make stew or soups I just dump in a jar. Good way to use up left over tomatoes and onions. I don’t remove the skin and sometime I will have to remove a skin from the soup pot.
Heather
I know Melissa already asked “”Do you use the water (that you boiled the tomatoes in to skin them) to put into the jars? And you answered that you could if the tomatoes were very clean.
However, I still would like to confirm: Was your water and/or puree liquid poured onto the diced tomatoes cold or hot? And if it was cold, do you have a water bath timing for hot water added onto the tomatoes?
Tiffany
Heather, my tomato puree was room temperature. I put the scraps into the blender and added it to the jars.
Robyn Comfort
I started growing fresh basil this year. Would I be able to added fresh basil to the diced tomatoes when I can them?
Tiffany
I’m really not sure Robyn. I’m not an expert in canning and I wouldn’t want to ruin your batch. I would *think* it would be okay since your level of acid for the entire jar should in theory be okay for adding a few herbs, but I would keep digging up research just to be on the safe side.
Kendra
If you’re going to add herbs, I would add dried ones. Fresh basil would look like cooked fresh spinach after the canning I would think, and probably not be very attractive. Plus, I think dried herbs are more concentrated, so you would need less to get the same flavor add. I’d also be worried about the acidity too. Botulism isn’t anything to mess around with. Check the Ball canning information or look online for your local extension office. They might have more information. 🙂
Charlotte
I don’t know if it is safe or not but I have added basil in the past — with no ill effects HOWEVER the basil looks black and uck-y. I have also added whole sprigs of rosemary which works pretty well. That said, I won’t do that again. I would recommend that you freeze chiffonade of basil or pureed basil in ice cube trays. That way when you open a jar of tomatoes, all you have to do is grab an ice cube or two of basil from your bag of frozen cubes and pop it into the pan with your tomatoes. I think the flavor of the fresh basil is far superior to dried. You also have basil to add to pasta or potatoes or soup or whatever else you want to add it to. I also freeze pesto and use it all through the winter. Hope this helps.
Judy V
Am going to give this a try…seems simple enough. Can I add some onions and green peppers for a stewed tomato version?
Tiffany
Sure! Just be sure to keep tomatoes the primary vegetable so your acidity level doesn’t drop.
Charlotte
I haven’t canned for 40 years and now that I am retired I am looking forward to it. When I did can, it was with my mother and/or grandmother. I don’t remember them adding lemon juice but they may have. Do you taste it? BTW, I have gotten more good advice from this website than any other I have used. Many thanks.
Tiffany
That’s an incredibly kind and encouraging thing to say Charlotte! It means a lot to me to hear this – thank you SO MUCH for sharing with me! As for the lemon juice, you don’t taste it. It’s to help increase the level of acid in the jar so you don’t get sick later. 🙂
Bob Gettings
I was raised on a farm in SW Pennsylvania and mom canned everything. I still have her Ball Canning book. Anyway, I’m retired now and picking up where mom left off and having a swell time of it. I just finished three quarts of diced tomatoes which came from ten pounds of tomatoes. My back feels it too. In another month I’ll be doing crab apple jelly. The neighborhood kids know of this and will be asking. I have already put up fourteen quarts of assorted pickles. Yum, yum. And stuffed two dozen banana peppers with hot Italian sausage. They are vacuum packed and frozen. And we have been vacuum packing and freezing sweet corn. Corn on the cob in January is delightful. I look forward to canning some pickled jalapenos but my plants are anemic this year. We’ll see.
Kristen Smith
Thanks for responding! The next morning the tomatoes had all redistributed through the jar like magic. I was one happy girl! Thanks for sharing.
Kristen
Hi. I just tried this process with raw diced tomatoes. I just pulled them out of the water bath after 85 minutes and all of the tomatoes have floated to the top of the jars with water underneath. 🙁 Did I do something wrong, or will this resolve after cooling? The jars are all pinging and sealing, they just look weird separated.
Kendra
This happens. When you are canning the tomatoes, they cook in the heat and will shrink up. I’ve ended up with air gaps at the top too, even though I’ve filled the jars all the way. I just went and checked on last year’s canned tomatoes, and the tomatoes eventually redistributed themselves through the liquid, because gravity. 🙂 My tip – I take the skins off before I can, so when I need tomato purée, I just give the diced tomato jars a good shake before opening. That usually is enough to pulverize the tomatoes inside for a rough purée. 🙂
Peggy
This floating to the top is normal. It doesn’t affect them at all. Once they’re cooled and you are moving them to a cabinet, just moving them redistributes them a bit.
Greg Ward
It’s simple if you think about it, when you wash your tomato’s I do it in the sink full of water normally. The tomato’s float, so when you can them, nothing has changed, the tomato’s will float to the top.
Melissa
Do you use the water that you boiled the tomatoes in to skin them to put into the jars?
Tiffany
I didn’t Melissa, but you could if your jars were clean!
Marjorie
you also need to be certain that your tomatoes were well washed, otherwise you could be filling the jars with bits of dirt. I canned tomatoes, bushels of them, for years to feed my family of 8. Now that I live alone, I buy them already canned but I look for San Marzano type as they have better flavor.
Guinan
Good Idea! This is sure to taste wayyy better than the tin canned ones!
Can anyone tell me how to turn this into ROTEL tomatoes? They aren’t sold here in the Netherlands. Thanks for your trouble!
Geri
Tomatoes with other Vegggies, like peppers, must be pressure canned to prevent botulism.
Tiffany
Unfortunately Geri, that’s not what the National Center for Home Food Preservation says: http://nchfp.uga.edu/how/can_03/tomato_water_pack.html
Marni
Just add jalapanino and onion simmer on the stove about 30 min. Then hot water can for another 30.that’s how I make home made rotel.oh and dont forget the salt and in this case about 1/4cup of vinager for 6 half pint jars
Mike D
Clear, concise and to the point. I now want to can my own.
I want to try this with local heirlooms that I love.
Tiffany
Thanks Mike! Let us know how it turns out!
Cindy
I have an overstock of tomatoes from my CSA, and my husband won’t eat them. I didn’t think of this, although I do make my own pickles (cucumber, zucchini and hot peppers) every fall! Thanks!
Tiffany
You’re most welcome Cindy!!
Jutta van der Kuijp
I dehydrated all the skins and made tomato powder out of it to add to food in the winter – nothing wasted!
Tiffany
Smart thinking!!
Bess
such a good idea .
thanks
Charlotte
I tried this. Great idea. And it didn’t take long. Watch them carefully. I sent some to my daughter (along with the mushrooms I had dried for her and she really liked them. Talk about thinking outside the box!!!
Jenifer
Heating the jars in the oven isn’t really recommended. (Something about dry heat and jar stability). Better to run them through your dishwasher and keep the dishwasher closed To keep them warm.
Also you can reduce or even eliminate the salt if you choose. It’s for flavor not safety.
Tiffany
Thank you for the tip Jenifer. I usually put mine in a pot of water, but as you can see, there’s already several pots going at once. 🙂
Sara
So if you don’t want to peel the skins off the tomatoes, can you just cut them up and add them to the jar without boiling them?
Tiffany
Yes! You don’t have to cook the tomatoes before canning them.
Amber
Hi Tiffany
Very informational ! I’m getting ready to can some more tomatoes before it’s too late! I like your simple recipe just wondering how come if I use water to fill jars it’s only 45mins boil time but if I use homemade tomato puree it’s 85mins?
Thanks Amber
Tiffany
Hi Amber! I can’t give you an exact answer on that because my guidance came from the FDA, but my best guess is that it would have to do with amount of solid food vs. water in the container.