Why do tomato plants have hairs? Garden Tips 2024

Save for later!

If you’ve ever handled a tomato plant, you may have noticed it has a rough texture. The cause of this roughness is the presence of tiny hairs.

Why do tomato plants have hairs: Along the stems and leaves of tomato plants you will find tiny hairs called trichomes. These hairs have a small gland at their tips that secrete a liquid that traps small insects, thus preventing them from eating your plants and passing on diseases. The hairs can also absorb nutrients and water.

What are the little hairs on tomatoes?

The little hairs on tomatoes are called trichomes. They cover the entire tomato plant, including the stems and the leaves.

Interestingly, the part of the tomato plant that grows underground also has trichomes on it. While this does not include the roots, any part of the stem that is buried under the soil will have trichomes.

Types of trichomes

There are two types of plant trichomes: non-glandular and glandular. Both types look the same but there is one major difference between the two.

Both glandular and non-glandular trichomes are small, just a few centimeters long. They are very thin and come to a point at the end.

The difference lies in the fact that glandular trichomes have a small gland at their tip, hence the name. This gland will secrete a liquid when triggered, either by touch or by recognizing that there is a pest or insect nearby.

Are tomato trichomes glandular?

Tomato plants have glandular trichomes. Even though non-glandular trichomes have a lot of benefits, the fact that tomatoes have trichomes that are glandular means they are better able to add protection to the plants.

As we’ll see in the next section, glandular trichomes produce a sticky liquid that traps insects. Furthermore, the liquid can actually be toxic to some types of bugs.

What’s the purpose of trichomes?

Protection from insects

One of the biggest threats to any type of plant in a garden is insects. While there are some beneficial insects, those that like to munch on tomato plants can weaken the entire plant as they chomp through stems and leaves.

There are two ways that trichomes help protect against unwanted insects.

First, the trichome hairs are not very pleasant to come into contact with. The rough texture will deter many insects and even plenty of larger pests.

Secondly, the small glands on the tips of trichomes will emit a liquid that is quite sticky. This substance will trickle down the plant and many small insects can become stuck in it.

If you’ve ever tended to your tomato plants and noticed a sticky substance on them, this is an example of the trichomes in action. In some cases, the glands produce a liquid that is toxic to certain kinds of pests.

Protection from rain

Water is necessary for plants but sometimes too much of it can cause devastation. While we can control how much we water our tomato plants, when it comes to rain, we are at Mother Nature’s mercy.

Trichomes add a layer of protection to tomato plants from an excess amount of rain. Rain will hit the trichomes and slide off them as they act as a barrier.

While some rain will pass through the tiny trichomes, the plants are spared the full brunt of the wetness. The result is that tomato plants will be less susceptible to rot and fungus.

Absorption of nutrients

When you plant your tomato plants, it’s recommended that you bury the bottom third of the plant in the soil. This is to encourage the plant to spread out and also to take advantage of the trichomes.

The tiny hairs will grow on all parts of the tomato plants, including parts of the stem that are underground. Even though they are under the soil, they are still working hard.

Trichomes will absorb both water and nutrients from the soil, leading to healthier plants. It’s like an extra set of roots.

Temperature Control

As we mentioned, trichomes are able to absorb water, and this is true whether the water is from underground or above. Trichomes will absorb water from both rain and hand watering.

They then store this water and release it into the plant when they sense that the rest of the plant is becoming dehydrated. This is an excellent way to keep your tomato plants healthy and it means you don’t have to continually water the plant throughout the day.

Sturdier Stems

When growing tomatoes, the use of a trellis or cage is important. Tomato plants have thin stems and once their fruit starts to grow, they can become off-balance.

Even though they are small, trichomes add a layer of stability to tomato plants. You should still provide an external method for support but having trichomes is one way that tomato plants have adapted to their construction.

Can I feel trichomes?

You might not have noticed that there are tiny hairs on your tomato plants, but you will most likely have felt them. Their texture isn’t exactly rough to humans, as the hairs are so small, but it is definitely not a smooth feeling.

While you may be tempted to touch the trichomes on your tomato plants, do so gently. The hairs are meant to protect against smaller pests and if you grab a hold of a tomato stem, you can break or damage the trichomes. They will grow back but before they do, you are depriving your tomato plants of much-needed protection.

Are trichomes poisonous?

The fruit on tomatoes is definitely not poisonous, so you can eat all the tomatoes you want. However, the secretion from the trichome glands is mildly toxic.

The good news, however, is that it is such a small amount that it isn’t really considered poisonous. You or your pets would have to consume a large number of tomato stems and leaves to notice any damage.


The tiny hairs on tomato plants are called trichomes and they serve an important function. They protect against insects, help absorb nutrients, and add stability to the plants.

Related Articles:

Save for later!

Leave a Comment