What Causes Tomatoes To Crack | Stop Tomatoes Split

Time to Read 5 Minutes.

Tomatoes are the most commonly used vegetable. One of the most common problems gardeners face is tomatoes cracking or splitting. If you ever notice this in your garden, your plant is under stress, and it is not a perfect growing condition. Ultimately you will not receive quality fruits. In this article, I’ll cover everything about why do tomatoes split?

This fruit cracking can happen before ripening or after harvesting. There are several causes for tomatoes to crack on vines or tops, and this article will cover everything about preventing tomatoes from cracking before ripening. Tomato plants are not hard to grow, but they require more attention and care.

If you notice one or two tomato skin cracks, you have to take necessary action to prevent this. Otherwise, it will further spread (it is not infected like a fungus) the entire harvest, and you cannot sell these crack tomatoes if you are a commercial farmer. So it reduces your profit.

What causes tomatoes to crack or Split?

Tomato plants are more sensitive to environmental changes, and the common reason is imbalanced watering, high sugars deposit on the fruit, and sudden climate change (drought stress). We can identify three conditions caused by tomato splitting, and the water, light, and temperature imbalance are the three elements.

Another possible cause of tomato cracking is the accumulation of high sugar content within the fruit because the high carbohydrate concentration increases pressure against the cuticle.

The rapid absorption of water.

The leading cause of tomato crack is the rapid absorption of water, and this quick water intake can happen mainly overwatering or under-watering.

Overwatering: Because of the high water content of the soil, the plant intake lots of water in a short period. Due to that excess water intake, the fruit cells and tissue grow faster than the outer tomato skin. As a result, the skin cannot keep up with the inner growth, and it cracks. This excess moisture level can happen either from irrigation or from rainfall.

Underwatering: Watering after the soil is extremely dry for too long is another reason for cracking tomato skins. When the plant does not receive water for a couple of days. While the plant is thirsty, it quickly takes in lots of water. This rapid water intake causes tomato skin to split. The cracking problem worsens when wet days are followed by dry days.

We can see tomato skin splitting issues mainly in the fall and watering after extremely dry soil, especially in hot summer.

Bright Sun.

Sunburn is said to be the leading cause of most tomato skins splitting. When the tomato fruit is exposed to direct bright sun for a more extended period, tomatoes split, which can usually happen in hot summer.

Sudden temperature changes.

Sudden temperature fluctuations can result in tomato skin splitting, and this is because the temperature difference causes the fruit to expand and the skin to tear.

Tomatoes are more prone to cracking if the temperatures in the morning and evening are drastically different. Having very hot daytime and freezing nights is another factor that causes cracks in tomatoes.

Excess nitrogen and less potassium.

Excess nitrogen (N) and less potassium (K) on the soil also cause tomato skin crack. Even a tomato is a heavy nitrogen feeding plant, too much not suitable for its fruits, and excess nitrogen makes the fruit soft and susceptible to cracking. Excess nitrogen may result tomato leaves turning brown.

Lack of Calcium.

We can see tomato fruit cracking due to a deficiency of calcium. When the fruit is in the development stage (green), tomato skins splitting can be seen if it receives less calcium. Generally, we can see blossom end rot as a lack of calcium.

Tomatoes grow well at pH level 6.5; when it drops below 5.5 or lowers, you may experience calcium deficiencies.

How to prevent tomatoes from cracking.

After I figured out the exact causes, the next step is, how to prevent tomatoes from splitting. We need to take the most appropriate actions depending on the situation.

How to fix rapid absorption water.

We can fix excess soil moisture by using well-aerated, loose, and well-drained soil. The recommended soil mix is peat moss/coir, perlite with compost, garden loam, or commercial potting mix. When the plant starts to produce fruits always maintain constant soil moisture using mulching and timely watering.

In a summer-dry climate, apply mulch to prevent tomato splitting. This reduces soil water evaporation and allows the plant to take in water throughout the day.

Another solution is to apply a drip irrigation system. This watering technique will control the amount of water, prevent excess watering, and ensure receiving water periodically.

Fix bright sun.

Avoiding excessive sun exposure in the summer can help prevent fruit cracking, so cover tomato fruits with a UV-cut film or sunblock shade cloth when they’re out in the sun.

Protecting the fruits, especially the green ones using 25-35% shade nets, can reduce spring and summer cracking.

How to fix excess nitrogen.

Adding sawdust or wood chips to potting soil absorbs the excess nitrogen. These two materials have carbon, and it absorbs excess nitrogen.

Another solution is top watering, and this will leach nitrogen deeper and reduce the top layer nitrogen level. Make sure that when watering, do not overwater tomato plants. We can organically improve the soil potassium (K) by adding banana peels to tomato soil.

Fix tomato calcium deficiency.

When you see a tomato cracking, you can apply eggshells tea, crushed eggshells powder to provide enough calcium for tomato plants.

Eggshells are an excellent organic fertilizer to boost calcium levels, although it takes some time to decompose. However, applying eggshell tea for tomato potting soil and wood ash can quickly increase calcium levels, especially by spraying on the leaves. This is because eggshell tea dissolves calcium in the water and accelerates plant calcium absorption.

Another quick calcium supply is applying Calcium Nitrate or agricultural lime (calcium carbonate). Agricultural lime can quickly increase soil pH levels. Always follow the manufacture’s recommended quantities. Directly applying calcium nitrate to soil is recommended to reduce skin splitting.

Calcium quickly enhances the soil pH level. Tomato plants need around 6.0 to 6.8pH levels for producing the best harvest. When adding a calcium supplement to the soil, always follow the manufacturer’s recommended level. Calcium can quickly increase the soil pH level, which is hard to reduce.

Why do tomatoes split after picking?

Tomato splitting can occur after harvest, and the cracked fruits can easily infect fungal and bacteria. Due to that reason, cracked fruits cannot be sold. Harvested tomato split occurs water content of the fruit, storage duration, and humidity level.

Ethylene regulates the ripening of tomatoes. Fruits that produce ethylene should not be stored in tomato containers, such as bananas, avocados, and apples, increasing ethylene exposure. Aside from that, ethylene is more sensitive to lower temperatures and relative humidity.

How to reduce harvested tomato splitting.

We can take several precautions to stop tomatoes splitting after picking. Applying plant cell growth and elongation hormone can reduce tomato splitting. Gibberellic acid (C₁₉H₂₂O₆) is recommended plant hormone that stimulates tomato cell division and elongation.

Another solution is washing the tomato fruits with calcium mix water. For this, you can use calcium chloride (CaCl₂) solutions.

Early Harvesting.

Tomatoes about to ripen can be harvested when the rainy season (or a sudden rain)  arrives, and this early harvesting will prevent them from splitting. After picking them up, place them in a paper bag. However, do not choose greens that do not ripen quickly