How to Pollinate Tomatoes in 3 Steps

Not sure how to properly pollinate tomatoes indoors? We've got you covered! Read on to learn how and when to pollinate your tomatoes the best harvests.

Unpollinated flowers simply fall off the plants without setting fruit, and failure to pollinate is one of the greatest causes of disappointment in growing tomato and pepper plants.   

Many plants, including tomatoes, peppers, cucumbers and melons, require pollination in order to produce fruit. When growing outdoors, this critical step is performed by wind, animals, bees and other insects. When growing indoors, we need to "be the bee" and perform this task ourselves if we want to enjoy those vine-ripened tomatoes in the middle of winter.
In broad terms, there are two types of pollination in the veggie garden we'll cover today:

  • Same flower pollination - Plants in this category include peppers, tomatoes and eggplants. In these plants, pollen just needs to be released from one part of a flower to another part in the same flower in order for pollination to occur. Wind is the most common pollinator here, literally "shaking loose" the pollen. Insects, like bees, also help with the vibration of their wings or the physical action of their climbing on flowers, moving the pollen around.
  • Multi-flower pollination - Plants in this category include cucumbers, melons and squash. These plants produce both male and female flowers. For pollination to occur, pollen must move from the male flower to the female flower. Generally, this is accomplished by insects flying or crawling from one flower to another.

As indoor gardeners, we usually have an absence of the three main outdoor pollinators: we don't have much wind or air movement, there aren't many animals in close contact with our gardens, and we don't have many pollinating insects in our homes. So we need to perform these vital tasks ourselves. We'll show you how in three easy steps.

Step 1. Determine Why Your Plants Aren't Pollinating

There are several reasons why your tomatoes or peppers might not successfully pollinate—and thus not produce the fruit you've been waiting for. Knowing the possible causes can help you pinpoint the most effective way to help your garden.

Tomato Pollination Requirements

Different types of tomatoes can require different climate conditions to flourish. For example, cherry tomatoes can develop fruit in a wider temperature range than larger tomatoes can.

For this reason, it's often helpful to research the ideal pollination condition for your breed of tomatoes to find out if there's something specific you can do for your tomato plant.

Generally speaking, tomato plant blossom drop may be affected by the following factors:

Extreme Temperatures

If the temperature becomes too hot or too cold, it can interfere with tomato plant pollination. Generally, tomatoes prefer a day-time temperature that stays below 85 degrees Fahrenheit, and a night time temperature that drops below 75 degrees Fahrenheit—but not below 70.

If the temperature surrounding your tomato plant isn't staying within that 70–85 degree range, consider moving your tomato plant to a different area of your home. If you can't move your garden, consider warming (or cooling) the room that contains your garden.

Strong Winds

Strong winds can harm your tomato plant's flowers, making it less possible for those flowers to one day turn into fruit. In an indoor garden, "strong winds" may look like a tomato plant placed too close to a strong fan, or even a tomato plant placed too close to an open window on a windy day. While a gentle breeze can help dislodge pollen so your plant can create fruit, too much air movement can put stress on your plant's flowers.

Dry Soil

Dry soil can stress tomato plants, which in turn can lead to less fruit—or no fruit at all.

However, if you're using an AeroGarden indoor hydroponic gardening system, you don't have to worry about dry soil. It's one of the many reasons we love hydroponic gardening. But if you're worried about soil-grown tomato plants, you can always dilute our patented liquid Plant Food to feed your traditionally grown plants.

A Lack of Insects

As we mentioned earlier, tomatoes self pollinating sometimes require bees, other insects, or gentle winds to help shake the flower. When the flower moves, it can then dislodge the pollen from the stems and complete the pollination process. If you have an indoor garden, you can help to mimic the role of a bee by gently shaking the string or stakes you're using to help your tomatoes stay upright.

We break down how to pollinate tomatoes in more detail in Step 3: Choose a Pollination method.

Pepper Pollination Requirements

Like tomatoes, your peppers can self-pollinate. However, they may need some extra help from you in setting the right conditions.

Your peppers might have trouble properly pollinating if:

It's Not The Right Temperature

Peppers require a specific temperature range to bloom. However, that exact temperature range can vary depending on what type of pepper you're growing.

For example, bell peppers typically prefer day time temperatures that stay below 86 degrees Fahrenheit, and evening temperatures that don't drop below 60 degrees Fahrenheit. That's a comfortable temperature range for many peppers, but hot peppers can actually like hot weather.

Consider researching the best temperature range for the specific type of pepper you're trying to grow, and then moving your indoor garden closer to a heat source—or farther away—depending on your plant's needs.

There's Too Much Wind

As with tomatoes, too much wind can harm your pepper plant's flowers and prevent them from producing fruit. This is less likely to prove an issue with indoor gardens, but it's worth checking to see if your indoor garden currently lives too close to a vent or a fan that could disturb its pollinating process.

Step 2. Understand Your Plant's Pollination Needs

Ultimately, helping your plants make the transition from producing blooms to producing fruit comes down to understanding what type of support your plant needs.

Do Tomatoes Need To Be Pollinated? What About Peppers?

Plants that self-pollinate typically only need a gentle shake to help their pollen move to where it needs to go to complete the pollination process.

Self-pollinating plants include:

  • Tomatoes
  • Peppers
  • Eggplants

While a gentle shake can help these plants self-pollinate, too much movement can cause them stress and potentially harm the flowers, just as a strong wind would. We'll break down different gentle techniques for pollinating plants below so you can feel confident supporting your plant's pollination needs.

What Plants Do Need to Be Pollinated?

Plants that don't self-pollinate typically rely on bees and other insects to move the pollen from the male flowers to the female flowers, which can then produce fruit.

These plants include:

  • Cucumbers
  • Melons
  • Squash

If you're growing these plants in an indoor area where they don't have access to bees, you may have to manually move the pollen between male and female flowers yourself. We'll walk you through that technique below so you can have a gorgeously blooming garden in no time.

Step 3. Choose a Pollination Method

Discovering what your plants need you to help them pollinate might feel like yet another item on your to-do list. But once you know how to do it, it's a quick, easy way to care for your plants—so that they can ultimately care for you.

We'll cover pollination techniques for plants that self-pollinate, as well as for those that need help moving the pollen from male to female flowers.

Pollinating Tomatoes, Peppers and Eggplants

With our tomatoes, peppers and eggplants, pollination is fairly simple and can be accomplished in a variety of methods, including:

  • Gently shaking or vibrating the plants or individual flowers a few times a week (daily is best) after flowers appear (see video below).
  • Use our Bee the Bee pollinator to vibrate the stem or individual flowers. A children's electric toothbrush is another great solution. This method is best for tougher pollinators like eggplants.
  • Directing a fan at your garden. A fan on your indoor garden has many benefits, including increased pollination.

Pollinating Cucumbers, Melons and Squash

With plants that have male and female flowers, we need to move the pollen from the male flowers to the female flowers. Many plants will produce a large amount of male flowers first, then the female flowers start to appear. You can tell the difference between male and female flowers by studying them closely. Male flowers are smaller and you can often see the pollen as "dust" inside the flowers.

Female flowers tend to be larger and often have a small, unfertilized fruit at their base. For example, with cucumbers, you can actually see a small ½ inch long cucumber at the base of the female flowers. If left unpollinated, this will drop off. If pollinated, it grows into a full sized fruit. With practice and observation, you'll get good at telling the difference.

To fertilize these plants, simply use a cotton swab or small artist's paintbrush to move pollen from the male flowers to the female flowers. This too takes some practice, but you'll know when you are doing it correctly as you start enjoying, literally, the fruits of your labors.

Grow Healthy Plants with AeroGarden

Playing mother nature and learning to pollinate your indoor plants is fun, easy and rewarding. Regular and active pollination results in far larger yields than are accomplished without it, so getting good at it is worth your time and attention.

Sometimes it can be difficult to tell if flowers are ready for pollination or if they have been pollinated, so this instructional video contains many pictures of pepper flowers in various stages of growth as well as detailed instructions on how to pollinate plants in your AeroGarden.