Why Are Tomato Flowers Dropping (Blossom Drop) And How To Take Care Of It?

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Quick Answer: Why Are Tomato Flowers Dropping And How To Take Care Of It?

The condition causing the dropping of tomato flowers is called blossom drop. It may occur due to temperature fluctuations, lack of pollination, relative humidity, strong winds, inappropriate fertilization, heavy fruit set, watering inconsistencies, and damage by pests. You may protect your tomato plants during hot weather, select the right tomato variety, and practice cultural measures to avoid blossom drops. 

In this detailed guide, I will throw light on different causes of the dropping of tomato flowers. I will also discuss various measures to take care of it.

I have used my experience of growing tomato plants and tips from gardens across the world to prepare this guide.

Shall we get started!

What is Blossom Drop?

Tomato plants may experience blossom drops that affect fruit yield. It is the loss of tomato flowers due to pollination and fertilization issues.

Tomato is one of the popular plants in my garden.

One summer, my tomato flowers started to dry up and fall off without setting any fruit. I thought, what is going on? 

The tomato flowers have to be pollinated within 50 hours. Otherwise, it may drop off. Read more on tomato pollination process here>

It is usually preceded by the yellowing of tomato flower stems.

The loss of tomato flowers is called blossom drop. It is because the interference in the pollination and fertilization process that may impact tomato yield.

Why Are Tomato Flowers Dropping?

Several factors, including environmental, nutritional, or cultural may stress the tomato plants. It causes the flowers to drop.

The main causes of tomato flower dropping may be nutritional, environmental, or cultural. It may also occur due to shallow watering, strong winds, insect damage, or heavy fruit set. 

Click on this video for more information:

You may read below to know more!

1. Temperature Fluctuations 

Tomato plants may tolerate extreme temperatures for a shorter period. If there are fluctuations in temperature for a longer time, it may cause the blossom drop.

Tomatoes grow well in daytime temperatures of 70-85oF. It may tolerate extreme temperatures for a shorter period.

But, the fluctuations in temperature for a long period may cause the blossom drop.  It may be because tomato plants experience stress.

High daytime temperatures over 85oF, high nighttime temperatures over 70oF, or low nighttime temperatures below 55oF may affect pollination. It will cause drying and dropping of flowers.

The longer the exposure of the tomato plants to high temperatures, the longer will be the flowering issues.

Once I planted my tomatoes too early in the spring, it affected the flowering process.

2. Lack Of Pollination

Tomatoes may require insects, wind, or handshaking to carry out pollination. Low insect numbers, extreme weather conditions, or lack of air may cause blossom drop.

Sometimes, blossom drop may occur due to the lack of pollination. The tomato flowers are usually wind-pollinated. It may occasionally require insects. 

But, the low number of insects or lack of air movement may inhibit the natural pollination process.

It may, in turn cause the tomato flowers to dry and drop.

3. Humidity Problems

If there is high or low humidity, tomato plants may experience stress and interfere with pollination. It may cause the flowers to dry and fall off.

Another stress that causes tomato flowers to drop is humidity problems. 

The optimal relative humidity preferred by tomato plants is between 40 to 70%. The fluctuations in humidity may cause pollen to become dry or sticky. It may not be suitable for effective wind pollination and cause the flowers to drop.

High humidity may encourage the growth of fungus and cause the pollen to clump.

In contrast, low humidity may cause sticky pollen and interfere with the release of pollen.

4. Strong Winds 

Excessive winds may cause the tomato flowers to dry and knock them off the plants. It may thereby affect the fruit yield.

The strong winds may cause the tomato flowers to dry. It may also physically knock them off the plant and reduce the fruit set.

5. Fertilization Issues

Both high or low levels of nitrogen fertilizer may cause blossom drop in tomato plants. High rates of nitrogen in soil affect pollination, whereas low levels cause deficit food reserves to support a plant.

Tomato plants require adequate nutrients and fertilization for ideal fruit production.

But, high or low application of fertilizers may cause blossom drop.

The excess nitrogen fertilization of the tomato plants may decrease flower formation due to increased vegetative growth.

On the other hand, low nitrogen fertilization may produce deficit food reserves that may not be sufficient to support a tomato plant.

6. Heavy Fruit Production

Sometimes, tomato plants produce many blossoms that compete for limited nutrients provided by the crop. So, they start aborting some flowers to survive.

Certain tomato plants produce more fruits and may not produce additional flowers. It may cause an imbalance of nutrients within the plants, and tomato plants may focus on survival. 

So, it starts to drop flowers as the available fruits start competing for limited nutrients.

However, after the initial crop is harvested, the nutritional status of plants will come back to normal.

The flower-dropping problem may resolve.

7. Watering Issues

Tomato plants have an extensive root system and require adequate watering to support them. Inconsistent watering may cause the soil to dry and blossoms to drop off their vine before they produce fruit.

Tomatoes require consistent watering to develop a healthy root system that may penetrate up to five feet. It is necessary to keep the root zone moist throughout the growing season.

Shallow watering may stress and weaken the plants. It may cause the tomato plants to drop their flowers and affect the fruit set.

8. Damage By Insects And Diseases

Certain varieties of tomato plants are more susceptible to damage from insects and diseases. It may cause the flowers to drop off the vine.

Tomato plants are susceptible to numerous diseases, including botrytis, heavy bacterial spot, or bacterial speck pressure.

It is also prone to various insect attacks. These factors may negatively affect the flowering and cause the flowers to drop.

How To Take Care Of Blossom Drop?

blossom drop

The blossom drop may be controlled by growing varieties suited for the climatic conditions, ensuring adequate fertilization, watering deeply, and keeping the tomato plants healthy. You may also help with pollination issues.

You may choose a suitable variety and follow cultural practices to avoid blossom drop.

However, it may be hard to control blossom drop due to environmental factors, including temperature and humidity. In such cases, you may have to wait for favorable weather conditions.

Check out this video on how to stop tomato flowers from dropping:

1. Protect Your Tomato Plants

You may protect your tomato plants using a shade cloth if they are exposed to long hours of sunlight. Alternatively, you may opt for row covers or plastic tunnels to provide ideal growing conditions.

Ensure that tomato plants receive the right amount of sunlight to reduce the stress on tomato plants. 

As blossom drop is a common problem in summer in my area, I provide some shade in the afternoon to protect my tomato plants. 

Quick Tip:

The University of Maryland suggests covering 30% filtering shade cloth over tomato stakes. It may increase the yield and size of tomatoes during the hot months. You may also use row covers or plastic tunnels to protect tomato plants.

2. Grow Suitable Tomato Varieties

Select the right varieties of tomatoes suitable for your climate and region. The best choices are early maturing or heat-resistant varieties that may tolerate extreme weather conditions.

Many gardeners suggest planting tomato varieties suitable for your region and climate. You may try growing early maturing or heat-tolerant varieties for good yield.

These varieties may tolerate the high day and night temperatures.

You may select the varieties by reading the descriptions in the seed catalog by looking for heat-set, hot-set, or heat-tolerant.

3. Ensure Pollination

Ensure that tomato flowers are pollinated to prevent blossom drop. You may use hand-pollination techniques or plant nectarine-rich flowers to attract more insects.

The tomato plants may need help with pollination to avoid blossom drops. You may simply shake the plants and distribute the pollen.

You may place a vibrating device behind the open flowers and shake the plant to distribute the pollen. Alternatively, you may collect the pollen and use a cotton swab to rub the pollen into the end of the flower stigma.

There may be no insect pollinators during extreme weather conditions. You may help attract more bees by planting nectarine-rich flowers besides tomato plants.

I came across this useful video on hand pollinating tomatoes:

4. Avoid Overfertilizing

Do not over-fertilize tomato plants. Use balanced fertilizers after doing a soil test to prevent blossom drop.

I prefer to use organic fertilizers with balanced nutrients for the best results.

Avoid overfertilizing the tomato plants. Many gardeners suggest doing a soil test before planting tomatoes to know the required amount of fertilizers.

5. Manage Pests

Ensure that tomato plants are healthy and disease-free. You may practice good pest control measures to prevent blossom drop.

I scout daily to check for pests or diseases. You may control blossom drop by practicing good pest control measures.

If you observe any symptoms, treat the disease asap.

But, if the plant is heavily affected, it is advisable to remove the plant to avoid the spread of infection.

FAQ’s

How can you tell if a tomato flower is pollinated?

You may observe the opened tomato flowers. It may be pollinated if the stem behind the flower remains green and enlarged. Also, you may notice many pollinators around the tomato plants.

Does blossom drop happen only in tomatoes?

No. It may also happen in peppers, snap beans, and other fruiting vegetables. It may occur when the plants are environmentally or culturally stressed.

Summary

Blossom drop may be a threatening problem affecting tomatoes. I hope this guide will help you identify the issue and also provide tips to control the problem,

I would love to hear about your experience in dealing with tomato blossom drop.

Do share this article with your friends and family who love tomato gardening!