What to Do When Tomatoes Won't Set Fruit? Causes and Solutions

Tomatoes can be used both as a fruit and as a vegetable, and they help enhance various physiological functions of the body, clear heat and detoxify, and promote metabolism. Although tomatoes are suited to being sown and grown in summer, they can now be grown in any season through greenhouse cultivation. However, this has also brought some problems, among which tomatoes failing to set flowers and failing to set fruit are the main issues. So how should these be prevented and controlled? Let's take a look below!

1. Control the greenhouse temperature

Tomato is a warmth-loving crop, so the temperature inside the greenhouse must not be too high. During the day, it must not exceed 30°C at most. If the temperature exceeds 35°C and lasts for more than two hours, it will affect the tomato flower buds. The nighttime temperature must not be lower than 12°C or higher than 18°C. If the nighttime temperature is too high, the tomato stems will grow excessively, causing flower drop. Artificial cooling should be carried out. In weather with higher temperatures and strong sun, shade the greenhouse at the hottest time around noon, or splash water inside the greenhouse for physical cooling. Lowering the temperature can help with fruit setting very well.

2. Spray growth regulators

Growth regulators such as chlormequat can be sprayed on tomato leaves to regulate the growth rate of tomatoes and make the tomato stems thicker, but they must not be used in excess. Before use, a small amount can be sprayed first as a test, and then the corresponding dosage can be determined according to the growth condition of the tomatoes. If the dosage is excessive, it will not only fail to promote tomato growth but will also inhibit tomato growth. Try to choose a sunny afternoon for spraying, because this can reduce the probability of phytotoxicity.

3. Remove leaves to protect fruit

If you find that the tomato plant has too many leaves, you can remove the leaves with better growth to protect the growth of the tomatoes. However, the number of fruits on each plant should not be too many either, because if there are too many fruits, it indicates excessive nitrogen fertilizer, and excessive nitrogen fertilizer causes an imbalance in the tomato's nutrient absorption. Also, too many fruits will cause nutrients to be absorbed by the lower fruits, while the upper fruits do not have enough nutrients to flower and set fruit, causing the upper fruits to drop fruit and drop flowers. During the flowering and fruiting period, attention must also be paid to reasonable fertilization, otherwise it will also cause uneven nutrition.

4. Supplement nutrient elements

If you find that the tomatoes are growing too fast, or that calcium deficiency is caused by rapid water loss in the tomato plant due to excessively high temperature, you can spray some foliar fertilizer containing trace elements such as boron and calcium. This can also reduce flower and fruit drop to a certain extent. And under conditions of excessively high temperature, you can also spray a little bit of flower medicine, which not only protects the flowers but also increases moisture.

The four points above are the methods for preventing tomato flower and fruit drop. Tomatoes have relatively high temperature requirements, and the latter three points are more or less aftereffects caused by excessively high temperature. Therefore, by controlling the temperature around the tomatoes and inside the greenhouse well in daily management, you can reduce or avoid the occurrence of flower and fruit drop.