What Causes Tomatoes to Split & Crack

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The sight of some of your growing tomatoes splitting and cracking after heavy rainfall can be frustrating. No matter what stage of the tomato's development they are in, this can happen.

The purpose of this article is to discuss the reasons that tomatoes split on the vine during the growing season, the environmental factors that cause it, and how it can be prevented.

What Causes Tomatoes to Split and Crack?​

Tomato skin cracks and splits when the soil's moisture level changes rapidly after heavy rain follows a period of dry weather. Due to this, the tomato's skin splits and cracks as it expands faster than it can grow.

The tomato can split on the vine at any stage of its growth, but as the color develops, it becomes more likely to split.

The resistance of some varieties is higher than that of others. One way to reduce splitting is to pick tomatoes at the breaker stage.

There are two ways tomatoes split. On the side of the tomato, you will see vertical splits or circular cracks that start near the stem.

Heavy rains may result in concentric cracking of heirloom tomato varieties, but it's a small cost to pay for great taste.

What Causes Tomatoes to Split & Crack

What is the problem with a split tomato?​

The split or cracked skin of a tomato makes it more susceptible to bacteria, fungi, and insects, which cause the fruit to rot or get eaten by pests.

It is more likely for a ripe tomato to split than a green one, and depending on the circumstances, it may not need to be thrown out.

The 6 best ways to keep tomatoes from cracking and splitting​

1. Make sure your tomatoes receive regular watering​

It is recommended that tomatoes receive one to two inches of water every week. During the summer, water your tomato plants every two days to ensure that they receive sufficient moisture.

The best way to water a tomato plant is to do it at the base so that soil does not splash onto the leaves, possibly spreading soil-borne diseases like Anthracnose, which leads to tomato rot.

In order to prevent blight issues, avoid watering the leaves & foliage at the top of the plant.

Watering your tomatoes regularly will keep the soil moisture even, preventing abrupt temperature changes when it rains.

To make the process easier, you can install a drip irrigation system.

2. It is important to provide tomatoes with proper drainage​

You can reduce the risk of soil disease by making soil mounds or raised beds for your tomatoes. The soil should be loose and not easily compacted.

To ensure that excess water drains away from potted tomatoes, make sure the pots have drainage holes at the bottom.

3. Make sure your tomatoes are mulched​

By spreading organic mulch around your tomato plants, you'll keep the soil moist when it rains.

There are many types of materials that can be used as mulch for tomatoes, including grass clippings, hay, straw, leaves, or compost. The ideal layer should be between 2 and 3 inches thick.

4. The best tomatoes to grow are those that are resistant​

If you are buying seeds or small plants, check the label to see if it states "crack-free".

A few varieties that are resistant to cracking are Rutgers, Marglobe, First lady, Sungold, Big boy, Big Beef, Red sun, and Burgess crackproof.

5. Make sure you pick your tomatoes before it rains heavily​

The flavor of your ripening tomatoes can be saved if you pick them before a rapid moisture change occurs.

As soon as the tomatoes reach breaker's stage, they start turning pink and can be picked. The ripening process will continue after picking breakers and fully mature green tomatoes.

It also allows the plant to concentrate its energy on producing other tomatoes by picking tomatoes at this stage.

6. Make sure your soil has enough calcium​

Your tomato will be able to better regulate how much water it takes up when your soil contains the right amount of calcium. The beginning of the planting season is the best time to add calcium.

Your tomatoes will also benefit from calcium if you want to prevent blossom-end rot.

As eggshells contain calcium, you can add them to your soil or compost, along with dolomite lime (calcium carbonate), hardwood ashes, Gypsum (calcium sulfate), and other calcium-rich fertilizers.

What Causes Tomatoes to Split & Crack

What To Do if your Tomatoes split?​

Harvest your split tomatoes as soon as possible. Rot, insects, and other pests are more likely to attack exposed fruit.

As split tomatoes are exposed, they don't last as long, so serve them as sauces, salsas, and salads by cutting around the cracks.

Is it safe to eat split tomatoes? Can cracked tomatoes be eaten?​

If you catch cracked or split tomatoes quickly, they're safe to eat. Cracked tomatoes with a sweet smell are safe to eat, but ones with a sour smell should be composted.

You can always use the rest of the tomato for salads and sandwiches after cutting off the cracked part.

If you follow these tips, you may be able to reduce or prevent tomatoes from splitting permanently. In your garden, have you ever encountered cracked tomatoes? Please share your experiences in the comments.
 
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digitS'

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My garden tomatoes may have splitting and cracking problems but it is seldom caused by Summer rain, which isn't all that frequent in the Inter-mountain West. Instead, it's my fault ;). I realize that even some large, commercial operations use drip irrigation but my overhead sprinklers provide nearly all the 1 1/2" of water each summer week.

One thing that I have read and as you note, is that tomatoes split because of the inability of the skin on the fruit to accommodate the change in water absorbed. However, this doesn't mean that only varieties with tough skin resist splitting. The flexible skin of some resists splitting.

Big Beef has always been a very good beefsteak choice in my garden. And, I can point out that Sun Sugar resists splitting better than Sun Gold and is similar if not quite the same. There is no doubt that of the varieties that I have grown, Yellow Pear was the most split prone! Repeated tries - because DW liked it 🥴 .

Yellow Jellybean is one of the tough-skin resistants. However! For in-garden snacking - where spitting is permitted ;) - it's a tasty treat.

Steve
 

ducks4you

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Since I can MOST of my tomatoes, if there is a split or any imperfection that opens up the skin, I put it in the fridge to keep it from rotting. Next canning session I pull those out, put them in boiling water to remove the skin, and cut out what I don't want. I treat them as precious commodoties. It is still growing/harvesting season, so there isn't time to do extra work on Any vegetable.
It is about time to take any tomatoes that have rotted on the vine and ferment the seeds for next year. If there are small, I send them to the lawn to fertilize the grass.
 

baymule

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My very favorite variety is Cherokee Purple. It has green shoulders and it will split. The taste is worth putting up with the splits, just cut them off, no big deal.
 

flowerbug

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Since I can MOST of my tomatoes, if there is a split or any imperfection that opens up the skin, I put it in the fridge to keep it from rotting. Next canning session I pull those out, put them in boiling water to remove the skin, and cut out what I don't want. I treat them as precious commodoties.

i don't like to waste any useable part of a tomato, but instead of boiling first and cutting away the splits and rotting stuff i cut that out first and then dunk the rest of it to skin. that ways i'm not putting potential gunk/rotting stuff in my dunking water. i also make a point of saving any that i have to do "surgery" on until all the rest of the ones in better condition are done so that i'm saving those for last.

any trimmings or rotting parts of the tomatoes go in the bucket that gets buried in some garden. i want to return as much to the gardens as possible as that helps keep the fertility going for future rounds of growing.
 

digitS'

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Circular rings are usually not as bad as splits. They are often near the stem.

Another stem end problem is hard, yellow shoulders. They show up on many of my tomatoes early in the season. I did some reading about that and see that high temperatures early in the fruit development stage is the cause.

That sure makes sense. And, there isn't much we can do about the weather. The good news is that the tomatoes seem to adjust and grow more normally as hot weather continues.

Steve
 

Zeedman

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I think those cracks are proof that tomatoes are the smartest vegetable. As they get older, people get wrinkles... tomatoes get wise cracks. :rolleyes:

Concentric cracking is rarely an issue for me, since those tend to heal over. The longitudinal cracks are the ones which grow wider, and let in insects or disease. Certain varieties (such as Russian Purple, (and some green-shouldered types) seem to be especially susceptible to this. I've dropped several otherwise good tomatoes because the spoilage was too high.

Although almost any tomato can crack under certain conditions, mulch has proven to be helpful. Because the mulch helps to retain soil moisture, it can reduce the wide fluctuations in soil moisture which aggravate cracking.
 
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Jane23

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My tomatoes generally develop the lines, though I think this is mostly due to the extreme heat. Though we just had a downpour, and three of my tomatoes split wide open and started to peal back, I know that was from the sudden influx of water.

I need a better watering system, but everything around my home is still under construction, so that is in the works. I hope for a new hose and a better water setup next year. That will make things infinitely better.
 

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