Hello, my dear friends of steemians and especially my friends of 
Tomato crops need large amounts of water to grow. It is advisable to water them very often, daily even in the warmer months.
When the irrigation is not controlled, allowing the soil to dry completely, when water is supplied, the roots absorb the precious element very quickly. If at the moment this happens and the plants already have tomatoes, they react increasing their size, but their skin does not adapt with the same speed and in the end it ends up breaking, creating the cracks.
To prevent this from happening to tomatoes, a drip irrigation system can be installed, and in this way they will receive water periodically and a better control of the amount of water will be taken, avoiding the flooding and excess of water at once. In addition you have to make sure that the soil is well aerated, spongy and draining properly. In addition, mulching is very beneficial because it maintains a certain degree of moisture in the soil and does not require as much water.
Other causes why tomatoes are cracked is because of the temperature difference between day and night. During the hot hours the tomato swells and during the cold hours its size decreases remarkably, for this reason they crack easily. Another factor that influences cracked tomatoes is the use of excess nitrogen. When the compost or fertilizer that is being used has an excess of nitrogen, it will affect the tomatoes. This is why it is important to know the nutrient needs of the plants that are grown, so they will not have diseases or suffer from pests due to excess or lack of nutrients.
The cracked tomato can be radial or concentric, depending on the crack follow a direction from top to bottom or around the fruit.
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How to prevent tomatoes from cracking:
To avoid cracking it is recommended:
• Watering plants constantly:keeping the soil moist and making sure that it is able to absorb water well.
• Maintain soil moisture by quilting techniques. It can be placed in a layer of volcanic clay and in this way it is possible to reduce the evaporation of the water.
• Place fertilizer whenever necessary: the indications specified on the product packaging must be taken into consideration and keep in mind that if a dose is given a little higher than indicated, a very high but weak plant will be obtained.
• Control temperatures: When the day is very hot, it is best to place shading mesh on the plants. If they are grown in greenhouses, it is convenient to open the windows for ventilation. When the crop is grown in orchards or pots you can choose irrigation by nebulization since it will refresh the environment.