Do Tomato Plants Self-Pollinate? (7 Ways to Hand Pollinate)


In the past few years, I have noticed that there are not as many bees around, but my tomato plants still seem to produce plenty of fruit.  I started to wonder if tomatoes are able to pollinate themselves, and if bees are necessary for pollination.

So, do tomato plants self-pollinate?  Tomato plants are self-pollinating, which means that a single tomato plant can set fruit by itself. A tomato plant does not need other tomato plants nearby to pollinate its flowers and produce fruit. This is because a tomato flower is perfect, meaning that it contains both male and female parts.

Just remember that self-pollination does not mean automatic pollination.  There are still factors that can prevent a tomato plant from self-pollinating. 

In this article, we’ll talk about what self-pollination means and how it happens. We’ll also talk about what can prevent pollination, and how to pollinate by hand in those cases.

Let’s begin.

Do Tomato Plants Self-Pollinate?

A tomato plant is self-pollinating, or self-fruitful, which means that it can set fruit by itself. This is because each flower on a tomato plant is capable of fertilizing itself by autogamy.

Autogamy means that the male part of a flower sends pollen to the female part of the same flower. As a result, a single tomato plant in isolation can produce fruit.

In fact, a single flower on a single plant can produce fruit by itself. This is possible because each flower on a tomato plant is perfect.

A perfect flower is one that contains both male parts (stamens) and female parts (pistil). The male parts produce pollen, and the female parts are fertilized by the pollen.

Since each tomato flower contains male parts, it can produce its own pollen. It does not need pollen from another flower on the same plant or a nearby plant.

Since each tomato flower also contains female parts, it is capable of producing fruit, as long as proper pollination occurs.

tomato flower
Tomato flowers are perfect – they have both male and female parts.

This makes self-pollinating plants, such as tomatoes, ideal for indoor gardening.  You can plant just one, and still get fruit.

However, one drawback is that self-pollinating plants cannot evolve to changes in their environment. This is because the same genetic material is found in the mother plant and in any later generations.

It is important remember that self-pollination does not mean automatic pollination.  There are still certain conditions that are needed for self-pollination to occur.

To tell if a tomato flower is pollinated, take advice from Ana over at growingreenhouse: look behind the flower! If the stem stays green and gets larger, you can be fairly certain that a tomato fruit is on its way to forming.

Why Does My Tomato Plant Have Flowers, But No Fruit?

If your tomato plant has flowers, but no fruit, then something is preventing proper pollination. There are many factors that affect pollination and fruit set in tomatoes, including humidity levels.

tomato flowers
If your tomato plant has lots of flowers, but no fruit, then extreme temperature or humidity may be preventing pollination.

High humidity means that the male part of a tomato flower cannot release its pollen. Low humidity means that the pollen will not stick to the female part of the flower.

Temperature is another factor that will impact pollination. According to the University of Missouri, daytime temperatures above 85 degrees Fahrenheit (29 degrees Celsius) or nighttime temperatures above 70 degrees Fahrenheit (21 degrees Celsius) will make pollen non-viable.

Also, nighttime temperatures below 55 degrees Fahrenheit (13 degrees Celsius) will reduce pollination rates. Temperatures this low may even cause blossom drop on tomato plants.

You can learn more about the coldest temperature tomato plants can tolerate in my article here.

Stress to the plant from pests or lack of water can also decrease pollination. You can learn more about why tomato flowers may fail to produce fruit in my article here.

Do Tomatoes Need Bees to Pollinate?

Tomatoes do not need bees to pollinate their flowers. Although bees can be helpful in pollinating tomato flowers, there are other ways to pollinate flowers (more on this later).

Bees are probably the first thing you think of when you hear the word “pollinate”, and for good reason. Out of all the pollinators (including birds and butterflies), bees are the most obvious.

bee on flower
Bees can help to improve pollination of tomato flowers, but they are not strictly necessary.

When a bee touches a flower, its vibrating wings cause the flower to shake. This shaking movement stimulates the male part of the flower to release pollen onto the female part of the flower, encouraging pollination.

Unfortunately, the use of pesticides has taken a toll on bee populations all over the world.  If you notice that you don’t have many bees in your yard, there are a few steps you can take to welcome them back to your area.

How to Encourage Bees In Your Garden

First, plant lots of different types of flowers to attract the bees. To attract bees throughout the season, choose a selection of varieties that flower at different times of the year.

Also, choose plants that are native to your area if possible. Native plants attract bees with flowers that are familiar to them.

Having a few little flowers on your tomato plants is one thing, but plenty of big, beautiful flowers will bring the bees in droves.  While the bees might come to your yard for the larger flowers, they will stop to pollinate the tomato plants as well.

bee on blueberry flower
This bee is busy at work, pollinating your garden.

Also, avoid using pesticides in your yard.  Even some common lawn treatments can hurt or repel bees.

Ask your neighbors if they will consider going without pesticides.  After all, it won’t help if you stop using chemicals while your neighbors continue to use them.

It will be easier to sell this idea to your neighbors if they also have a garden that needs pollination.  If your neighbors are not gardeners, offer them some of the vegetables you get out of your garden as a gesture of goodwill.

Finally, you can get into beekeeping if you have an interest in it.  Since your plants are closest to the hive, beekeeping basically guarantees that your plants will be pollinated.  (It also means that you might get a nice harvest of honey each year!)

One last thought here: if you have row covers protecting your plants, be sure to pull them back once in a while. Otherwise, bees will not have a chance to do their work of pollination!

Can Wind Pollinate Tomatoes?

Wind helps to pollinate tomatoes, even in the absence of pollinators such as bees. The method is similar: the wind causes tomato flowers to move, and that stimulation causes the male part of the flower to release pollen onto the female part of the flower.

wind vane
Looks like the wind is really going here!

There is nothing you can do to create wind outdoors to pollinate your plants.  However, if you are growing tomatoes in a greenhouse, you can use a fan to create a breeze that will help with pollination.

Also, be sure to leave the greenhouse door open on a windy day.  Then the wind will do the work of pollination for you.

greenhouse
Leave the door of the greenhouse open on a windy day.

If you are growing tomatoes in your home, open the windows to let in a breeze on a windy day. On a still day, you can still use a fan to create a breeze to pollinate your tomato plants.

Do I Need to Pollinate My Tomato Plants?

With all of this talk about self-pollination and natural methods of pollination, you might be wondering why anyone would need to pollinate a tomato plant by hand.

First of all, pollinating by hand will speed up the process, so that your plants produce fruit sooner.  In a cold climate with a short growing season, a few days can mean the difference between a good harvest and losing lots of fruit.

Roma tomatoes
Hand pollination can lead to more tomatoes from your plants. You do want more tomatoes, don’t you?

Also, pollinating by hand will increase your tomato yield per plant so that you can harvest more fruit every season.  If you leave things to chance, the wind or the bees may not pollinate as many flowers as you could by hand.

This is especially true if the wind is still when your plants flower, or if the bee population in your area is declining.

How To Hand Pollinate Tomatoes

There are several methods you can use to pollinate your tomato plants by hand.  All of them boil down to the same thing: you are using movement to stimulate the flowers so the male part releases pollen onto the female part.

Pollinate Tomatoes With An Electric Toothbrush

Don’t worry – you don’t have to use your own toothbrush to pollinate your tomato plants!  You don’t even need to buy an expensive one.

Just get the cheapest electric toothbrush you can find – even be an old one that a friend or family member is throwing away. The bristles don’t need to be intact, since we are more interested in the vibration of the toothbrush.

electric toothbrush
The vibration of an electric toothbrush simulates a bee’s buzzing wings to promote pollination of tomato flowers.

First, turn on the toothbrush.  Then, touch it to the back of the flower, to cause the male part to release the pollen.

Sometimes, you will see a cloud of pollen coming out of the flower. This tells you without a doubt that the toothbrush is working.

The vibration of the toothbrush mimics the vibration of a bee’s wings and acts in much the same way.  The more thorough you are about touching every flower, the better your chances of getting more tomatoes at harvest.

You can repeat this process multiple times during the season. In fact, you can do it every day if you want.

Since air temperature and humidity affect pollination success, try using this method at different times of the day to hedge your bets.

Pollinate Tomatoes with a Q-Tip, Toothpick, Pencil, or Stick

This method is a little cheaper than the electric toothbrush.  The idea is to take your Q-Tip (or toothpick, pencil, or stick) and gently push up (or down) on the flower, moving it slightly out of place.

toothpicks
You only need one toothpick to pollinate your plants.

Then, let the flower go.  When it springs back into place, the movement and vibration will cause the male part to release its pollen.

Although this method is cheaper than an electric toothbrush, it will probably take more time per plant. However, it won’t take too long to hand pollinate a few small indoor plants with a Q-Tip.

Pollinate Tomato Flowers with a Paintbrush

You can also pollinate tomato flowers with a paintbrush. Simply use the bristles to swirl around the inside of the flower.

paintbrushes
A paintbrush is yet another tool that you can use to pollinate tomato flowers by hand.

The movement should encourage the male part of the flower to release its pollen. The bristles might also help the pollen to make its way to the female part of the flower.

Pollinate Tomato Flowers with a Tuning Fork

If you are a piano player or musician, you might like this method, and you are more likely to have a tuning fork lying around.  Just tap the fork on a piece of metal or wood to get it vibrating.

tuning fork
A tuning fork – not just for pianos!

Then, use it like you would use the electric toothbrush.  Touch the fork to the back of each flower while it is vibrating to release the pollen.

Pollinate Tomato Flowers with a Leaf Blower

Remember how you can use a fan in your home or in a greenhouse to provide a breeze for tomato flower pollination?

Well, here is a method that will let you kick it up a notch and take pollination to the next level.

Simply use an electric or gas-powered leaf blower to provide a strong wind to help your tomato flowers with pollination. You can learn more about this method (and the positive results achieved with it) at the University of Maryland Extension website.

leaf blower
You can use a leaf blower to produce a strong breeze that can stimulate pollination in tomato flowers.

Pollinate Tomato Flowers By Shaking the Plant

This method doesn’t require any tools, and it mimics what the wind would do.  All you need to do is move the tomato plant back and forth to stimulate movement of the flowers in the wind.

This method will be difficult to use if the tomato plants are tied to stakes.  It will also cause the stems or branches to break if you are too aggressive with the movement.

Pollinate Tomato Flowers with Tomato Blossom Set Spray

Tomato blossom set spray is sometimes called a pollination spray. However, this is a misnomer, since pollination sprays do not really cause pollination.

Commonly used in commercial greenhouses, these sprays artificially cause the flower to start producing fruit – without actually releasing any pollen. Thus, tomato blossom set spray bypasses the entire pollination process.

You can learn more about how blossom set spray works in my article here.

One drawback of a pollination spray is that although the resulting tomato fruit may form properly, the seeds will not. If you like to save seeds, this is not a pollination method you want to use.

Also, tomato blossom set spray is probably not a method you want to use if you are an organic gardener.

Conclusion

By now, you know what self-pollination means and how you can help your tomato flowers to produce fruit, either by natural or artificial means.

I hope you found this article helpful.  If so, please share it with someone who can use the information.

If you want to read some of my most popular posts, check out the “Best of GreenUpSide” page here.  Enjoy!

~Jonathon

jonathon.david.madore

Hi, I'm Jon. Let's solve your gardening problems, spend more time growing, and get the best harvest every year!

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