Why Tomatoes Split and Ways to Prevent It

Tomatoes splitting open is a common problem that can affect any gardener growing this popular vegetable. There are several potential causes of split tomatoes, but the good news is that with some care and preventative measures, you can minimize and often avoid this issue altogether.

What Causes Tomatoes to Split?

There are a few key factors that can lead to tomatoes splitting:

Irregular Watering

Fluctuations in soil moisture is one of the top reasons tomatoes split. After a dry period, thoroughly soaking the soil with water can cause the tomato fruit to swell and crack open as it expands faster than the skin can handle.

To prevent this, aim to keep soil moisture consistent with regular, even watering. Mulching around the base of tomato plants also helps maintain steady moisture levels.

High Rainfall

Just like sudden watering after a dry spell, heavy rainfall after a drought period can also cause splitting. The tomato skin simply cannot stretch fast enough when there is a rapid influx of water.

There’s not much that can be done to control natural rainfall, but protecting plants with row covers, tunnels, or greenhouses can help shield them from sudden heavy downpours.

Low Calcium Levels

Calcium strengthens tomato skins and walls, helping make them more elastic and better able to handle fluctuations in size. A calcium deficiency can leave tomatoes prone to cracking.

Applying a calcium-rich fertilizer following packaging directions can help prevent low calcium levels. Organic options include crushed eggshells, bone meal, and lime.

Fast Growth

Tomatoes that experience a growth spurt, especially after a period of drought or cold temperatures, are vulnerable to splitting. The rapid expansion stresses the skin and causes cracks.

Promoting steady, moderate growth by maintaining even soil moisture and fertility can help avoid growth surges that lead to splitting.

High Humidity

Humid conditions can contribute to splitting by causing excessive foliage growth. This puts more stress on the tomatoes as the plant struggles to supply nutrients and moisture to support all the plant growth.

Pruning leaves and vines to improve air circulation and light penetration can help cut down on humidity levels around tomato plants.

How to Prevent Tomatoes from Splitting

Now that we’ve covered what causes tomatoes to split, here are some of the top techniques to help avoid and minimize the problem:

Water Regularly

As mentioned, inconsistent watering is a common culprit, so aim to water plants at the same time each day, providing 1-2 inches per week. Use drip irrigation or soaker hoses rather than overhead sprinklers.

Avoid Excess Nitrogen

Too much nitrogen fertilizer triggers rapid, leafy growth that puts stress on tomatoes. Follow fertilizer labels and focus on even nutrition across the NPK spectrum.

Monitor Calcium Levels

Watch for signs of blossom end rot, which indicates low calcium. Supplement as needed with bone meal or crushed eggshells to strengthen skin cell walls.

Consider Variety Selection

Some tomato varieties are more prone to splitting than others. Opt for crack-resistant types like Celebrity, Defiant, and Big Beef.

Check Fruit Frequently

Inspect tomatoes often for any small cracks developing so you can harvest them promptly before the cracks worsen.

Harvest with Care

Avoid squeezing or dropping ripe tomatoes when picking them. Handle gently to avoid bruising or other physical damage.

Frequently Asked Questions

Why do my tomatoes split after it rains?

Heavy rain after a dry period can cause tomatoes to split from rapidly expanding after drought conditions. The tomato skin doesn’t have time to adjust to the sudden influx of moisture.

How can I use split tomatoes?

Split, cracked tomatoes should be used promptly before rot sets in. They can be enjoyed fresh in salads and sandwiches, cooked down into sauces, juices or soups, or preserved by canning or freezing.

Do heirloom tomatoes split more easily?

Yes, large beefsteak and heirloom varieties tend to be the most susceptible to cracking. Their thinner skins and softer flesh make them less able to withstand fluctuations.

Should I remove flowers to prevent splitting?

Removing some flowers can help reduce total fruit load, lowering the plant’s stress and demands for moisture and nutrients. But moderate pruning is usually sufficient.

What is the white part inside a split tomato?

The white tissue visible inside a cracked tomato is the inner wall of the fruit’s locules that divided the interior into separate seed compartments. It is perfectly normal and safe to eat.

Can you still eat a tomato that has split?

Yes, split tomatoes are still safe to eat as long as the flesh inside looks fresh. Just trim off any cracked skin and damaged areas. Use promptly before spoilage occurs.


Preventing tomato splitting requires paying close attention to soil moisture, plant nutrition, tomato varieties, and handling. But the effort is well worth it to be able to enjoy a bountiful, unblemished tomato harvest. Just be diligent about inspection so any fruits that do crack can be harvested promptly. With some care and the right prevention tactics, you can minimize frustrating tomato splitting.