Tomato Blossom Drop: Why It Happens and What to Do

If your tomatoes are dropping blossoms or the flowers wither and die, there are several reasons, all of which are related to stress. The stressors can be environmental, nutritional, or a combination of the two.

What Causes Tomato Blossom Drop?

Nitrogen

Too much or too little will stress the plant. Always follow the instructions on your fertilizer. Use an organic, slow-release fertilizer and compost instead of using quick-release, synthetic fertilizers.

Temperature

Day temperatures above 90 degrees and night temperatures above 70-75 degrees can interfere with pollination and fruit set. Research indicates that the higher night temperature has more of an influence. In this case, it can be tough to keep your plants cooler during the day and night cycles. Shade cloth may help prevent direct sun and hot temperatures from burning your plant during the day, and making sure to water early morning and later in the evening will allow your plant to absord moisture and keep the soil a bit cooler.

Poor Pollination

Tomatoes are self pollinating and rely on wind or other vibrations to shake pollen free. When humidity is high (above 80%) it can cause pollen to clump, and when humidity is low (below 40%) it can dry out the stigma, preventing pollen from sticking. In addition, lack of air movement or lack of pollinators in your area could prevent proper pollination.

Excessive wind, stress from insects or disease, lack of light, and excessive pruning are also reasons to explore if you’re experiencing blossom drop. Spend some time in your garden and see if you can identify the reason. And if you have any questions, feel free to reach out! Bring in pictures of your plants, and we will do our best to help diagnose your tomato plants and help you come up with a solution!