Do Mexican Butterworts Eat Gnats?

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Gnats are annoying persistent pests and getting rid of them can be a real challenge. One way to do it is with a carnivorous plant like Mexican butterworts. They not only eat flies but can also be effective when it comes to getting rid of fungus gnats. However before you get one there are some things you have to consider.

Mexican butterworts secrete sweet smelling, sticky mucus on their leaves which attracts gnats. Once a gnat is trapped, the plant releases digestive enzymes to eat it.

How Mexican Butterworts Catch Gnats

The leaves of butterworts – or pinguicula – have glands that produce mucus. This substance has a sweet, fruity scent that fungus gnats love. Not just gnats but other insects such as well. We will use gnats as examples her but butterworts use the same method to catch all prey,

There are many ways to get rid of fungus gnats, but you can use butterworts because they work as well as any. Aside from gnats these carnivorous plants will also catch crickets, wasps and other insects.

Pinguicula plants use considerable resources to produce mucus, but the trapping process is straightforward. When a gnat smells the mucus, it will look for the source. Once the insect lands on the leaf and tries to eat, it falls into the trap.

The mucus is very sticky and makes escaping difficult. The more the gnat tries to get out, the more it triggers the leaf glands to release more mucus.

The plant will then release its digestive enzymes and will start eating its prey. Sometimes the plant waits until the prey has died from suffocation In other cases butterworts release their enzymes when the insect is completely trapped, regardless if it is alive or not.

Digestive Process

Even if the gnat was still alive, the digestive enzymes are going to break its tissues down. Once dissolved, butterworts will eat and absorb the gnat and its own digestive enzymes.

As its tissues are broken own, it is converted into a solution that contains amino acids and other elements. Butterworts extract nitrogen and other nutrients from this solution and use them the same way houseplants use nitrogen from the soil.

The process above is repeated for every gnat that gets trapped on its leaves. It is very simple but effective and bears a strong resemblance to the way drosera lures prey. After consuming these nutrients, the pinguicula stores this extra energy or puts it to use.

the same thing happens when you feed butterworts with Picky Neb Dried Mealworms. Of course the worms here will not struggle, but the digestive process will be the same. These dried mealworms also provide butterworts with the nutrients it gets from insects.

Why Mexican Butterworts Eat Gnats

While we benefit from butterworts, it is byproduct of their own needs. These plants consume gnats and other insects because they are the best sources of nutrition.

Pinguicula naturally grows in bogs and fens where the soil is moist, acidic and lacks nutrients. However, insects abound in these locations and they have the nutrients that these plants require.

It is possible for butterworts to survive without eating any gnats or flies. Their primary source of energy is glucose which they can make through photosynthesis. Under the right conditions, it is probable for butterworts to live on just glucose, light and water.

But nutrients provide an additional boost, particularly if you want to use pinguicula to get rid of gnats. The mucus its glands secrete requires plenty of resources. Nutrients provide the additional supply butterworts need to make this substance.

So while butterworts do not necessarily have to eat fungus gnats to stay alive, they benefit a lot from it. Whenever a bug is eaten, a pinguicula gains nutrients. These nutrients are used to make more traps which allows the plant to catch and eat more prey.

If your butterworts are catching a lot of gnats, you may be wondering if there will be conflict between nutrients and glucose. Is it possible for pinguicula to have too much glucose and nutrients?

It is very unlikely. Butterworts will only eat as many insects as it can handle. Plants make glucose and they will only produce as much as is needed.

Glucose and nutrients have similar functions but there is no conflict here. Glucose is the primary source of energy while nutrients serve as additional supply. One way to look at it is to think of glucose as food and nutrients as supplement, though of course gnats and other insects can also be considered food.

Are Butterworts Effective Gnat Controllers?

Carnivorous plants like butterworts are effective gnat controllers. Do not be surprised if you see a lot of gnats and other bugs caught in its leaves. Even a small pinguicula will catch a lot of bugs if it produces enough of the mucus.

There are many types of butterworts but they all catch and eat gnats. For the best results, buy your pinguicula during spring or summer.

Mexican butterworts drop their carnivorous leaves during winter and turn into succulents. They cannot eat bugs during this period, but that is not a problem as gnats are most active in spring and summer.

All you have to do is place your pinguicula close to where the gnats gather. Just leave the plant there and it will not be long before you see a bunch of them stuck on the leaves, struggling to escape.

The number of gnats a pinguicula can catch depends on its size. The larger the plant and the more leaves it has, the more gnats it will catch. If you have a lot of fungus gnats, it is a good idea to keep a few butterworts in your garden. If you prefer a more permanent solution we recommend Summit Gnat Spray which works quickly and safely.

The health of your plant also makes a big difference. A robust pinguicula produces more mucus and traps more insects. A sick one will conserve energy and will not be able to produce enough mucus.

As long as your butterworts are in good condition they will catch a lot of gnats. The nice thing about this is you do not have to do anything. If your pinguicula is outdoors -or indoors situated on an open window- these insects will be drawn to the mucus.

Do not worry about the plant catching too many gnats or overeating. Butterworts only eat insects when they need nutrients. If the plant has had its fill, insects caught in its leaves will likely not be eaten. However, the mucus will eventually suffocate them.

How to Make Butterworts Catch More Gnats

For butterworts to remain effective gnat repellents, you have to provide proper care. As mentioned earlier you should get your pinguicula in spring or summer so it is ready to catch and eat insects. You can also buy Mexican butterworts during winter but they will be in dry dormancy.

Sunlight. Butterworts love sunlight, especially direct light in the mornings. You may leave them under full light provided it is not too hot. If the temperature is no more than 86 F then that is fine. You have to move the plant under shade if the temperature climbs up to 90 F or higher.

Water and humidity. Grow the plant in an environment that is as close to its natural habitat as possible. In general that means mildly humid and sufficient light. You do not need to install a humidifier. unless it is really dry and hot. Just place the potted plant close to a saucer full of water. This will be enough to moisten the atmosphere and keep the plant in good health.

Do not fertilize the soil. Let your pinguicula get its nutrients from insects as that is enough. As for watering, just keep the soil damp. Do not pour too much water as it could drench the roots and cause it to rot.

Butterworts undergo change during winter. Temperate species go through dormancy and discard their leaves. Tropical butterworts as stated earlier, turn into non-carnivorous succulents. Care for your pinguicula accordingly and provide the appropriate environment.


Butterworts can be very effective in eliminating fungus gnats, and they need little maintenance too. Not only will your pinguicula get rid of pesky gnats, but they also receive plenty of nutrients in the process.