How to Pollinate Tomatoes? (When & Why It’s Important)

How to Pollinate Tomatoes? (When & Why It’s Important)

Depending on the type of tomato plant you’re growing, you could harvest upwards of 30 tomatoes on one plant. While you might plant tomatoes in the garden and forget about them, you might not realize that their flowers aren’t pollinating until you see that the plants aren’t producing any fruit. 

You can tell that your plants aren’t self-pollinating by checking the stems located behind their flowers. If they’re yellow in color, this indicates that your plant isn’t going to produce tomatoes. The stems should be green and enlarged, as these indicate healthy fruit production.  

So, what do you do if your tomato plants aren’t producing fruit? Maybe you’ve been doing everything right with your tomato plants, such as watering them properly, but your tomatoes still don’t bear fruit. Here’s everything you need to know about how to pollinate tomatoes so you can jumpstart their production. 

Can a Tomato Plant Pollinate By Itself?

Can a Tomato Plant Pollinate By Itself?

Usually, tomato plants are capable of pollinating themselves. They tend to do this most of the time. This is because the flowers contain both male and female parts within the same flower. During pollination, the plant’s anthers, which produce pollen, wrap themselves around the female (pistil) part of the flower.

However, there are some obstacles that can get in the way of this natural process and prevent it from happening. Since the pollen produced by tomato plants is sticky and can become even stickier in high-humid regions, it has to be loosened from the stamen (male part) of the flower to fall onto the female parts of the plant; otherwise, pollination won’t occur properly.

Usually, insects such as bees that are attracted to tomato plants or a strong wind are enough to achieve this.

Although you might assume that honeybees are effective at pollinating tomatoes, bumble bees work so well for this purpose. This is because their bodies vibrate when they’re close to the tomato flowers, and this helps to loosen the pollen. 

Since the flowers hang down from the stems of the tomato plant, the bee will hold onto the flower and vibrate to loosen the pollen. It’s not just bumble bees that do this, but also carpenter bees and native bees. Honeybees just don’t do this as effectively as these other types of bees. If pollination doesn’t occur, the flowers on the plant will die and fall off the plant. 

What complicates matters is that there’s also a limited time in which the tomato flowers have to be pollinated – this has to occur within 50 hours of the flower appearing on the plant! If your tomato plants are exposed to temperatures higher than 85°F (29.4°C), this can destroy their pollen.

If you have tomato plants in your garden and they’re not producing fruit, this is because they’re not being pollinated. You might wonder what you can do to help the tomato pollination process along.

One of the things you can do is encourage more bumble bees to come to your tomato plants. Seasonal planting is recommended when you have a mix of early and late flowers in your garden to make the nectar season last longer, attracting more pollinators such as bumble bees.

Some plants attract bumble bees more than others, so you should consider planting them in your garden close to where you’re growing tomatoes, as they will help the bees to pollinate your tomatoes. Examples of flowering plants include:

  • Daisies. Because these plants have flat petals, they attract large bees, such as the red-tailed bumblebee. 
  • Honeysuckle. This flowering plant attracts the garden bumble bee, which has a long tongue, so it likes flowers such as honeysuckles that have long tubes. 

How to Pollinate Tomatoes By Hand

How to Pollinate Tomatoes By Hand

Since your tomato plants have both male and female parts in their flowers, you can do several things to pollinate your tomatoes by hand. This is especially important to do if your tomatoes are kept indoors or in a greenhouse where they’re not exposed to pollinators and winds that can loosen their pollen.

Here are the most effective methods of self-pollinating your tomato plants and how they work. 

Gently Shake the Tomato Plants 

You can pollinate your tomato plants by gently shaking them to dislodge the pollen from their flowers. The best way to do this is to tap the top of the flower with a finger or pencil so that the stem of the flower will spread more pollen to both its male and female parts. 

Use a Fan 

If your tomato plants are indoors, you can make use of a fan to circulate more air to the flowers as this will mimic a natural wind outside. This works especially well for tomato plants that are on balconies or in an enclosed patio, as you can make the most of directing the flow and speed of air so that it has the most effect.

Fans can be useful in greenhouses, too, so that you can enhance air circulation. Set them up within close proximity to your tomato plants so that the breeze will be able to move the pollen around. 

Use a Vibrating Toothbrush 

To mimic the vibrations produced by a bumble bee, you can use a vibrating toothbrush to pollinate your tomato flowers. By placing this device along the tomato plant vine, its vibrations can help to loosen the pollen located in the flowers. What’s good about this method is that the head of the toothbrush is small so that it will fit into the tomato flowers. 

Use a Cotton Swab 

Some gardeners prefer a more meticulous method, which involves the use of a cotton swab. You have to collect the tomato plant pollen in a small container with a cotton swab, then use the swab to rub the pollen onto the end of the stigma of the flower. The stigma, which is the female part of the tomato flower, is the cone-shaped section of it that’s located in its middle.  

Spread Pollen with a Paintbrush 

If the cotton swab doesn’t work or the pollen is so sticky that you require a softer approach, you should get a soft-bristled paintbrush (just make sure it’s clean if you’ve used it recently!) and push it inside the flower so you can brush its petals. Make sure the paintbrush is small enough to fit into the flower. Once it’s collected pollen, spread it onto the flower’s stigma. 

It’s also good to choose a paintbrush that has natural instead of plastic bristles as this will ensure the pollen can better stick to it and be spread by it. 

Use an Electric Pollinator 

If you don’t own an electric toothbrush, you can purchase a product that will pollinate your tomato plants for you. An example is the VegiBee Garden Pollinator, that’s available from Amazon. What’s great about it is that it has five speeds, so you can find the best vibrating speed for the most effective pollination. It’s also rechargeable. 

How Often to Hand-Pollinate Tomatoes?

How Often to Hand-Pollinate Tomatoes?

You should pollinate your tomatoes by hand every few days. You want to ensure that you pollinate all the flowers and repeat the process every three days until the plants stop producing their flowers.

The best time to pollinate your tomatoes is on a sunny day when there’s not a lot of humidity in the air so that the pollen won’t be too sticky to handle. You will know that you’ve succeeded in pollinating your tomato plants if you can see that the flowers on the plants are starting to shrivel up and fruits are being produced on them.  

No matter what tomato hand-pollination method you choose for your tomato plants, you should be careful not to engage in cross-pollination. If you’ve got different tomato varieties in your garden, you need to avoid using the same brush or cotton swab to pollinate all of them as this will cause cross-pollination.

So, always rinse the item in alcohol to clean it properly before using it on a different tomato variety, or use a completely new and clean item. 

Conclusion

If your tomato plants aren’t self-pollinating, you can help the process by using various methods to pollinate them so they’ll grow fruit. This includes the following: 

  • Gently shaking the tomato plants and tapping their flowers. 
  • Encouraging more bees to come to your plants. 
  • Using a cotton swab to transfer the pollen onto the stigma of the plant’s flowers.
  • Creating vibrations that loosen the pollen, such as with an electric toothbrush. 

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About The Author

Gina Harper grew up dreaming about farms and growing her own food. She began an urban garden to feed herself and turned it into an incredible hobby. Gina is here to teach you everything from raised beds to container gardening, how to keep plants alive and well in a smoggy city, and the works. It’s time that we carve our own piece of green earth and reap what we sow—she’s here to help you with that.