The 6 Causes Why Your Venus Flytrap Won’t Close

In 1875, Charles Darwin wrote that the Venus flytrap “is one of the most wonderful plants in the world.” Darwin was awe-inspired by how the flytrap could move without muscles or nerves. But what do you do if your Venus flytrap won’t close? Here are all the reasons your flytrap might not close and what you can do about it.

Venus flytraps will not close due to 1) unsuitable substrate, 2) underwatering, 3) lack of distilled water, 4) inadequate sun, 5) overfeeding, and 6) excessive handling. Prevent this by planting it in sphagnum moss, providing adequate water, using distilled water, providing 6–12 hours of direct sun, and not overfeeding or overstimulating the plant.

Is your flytrap not closing? I feel your concern, but don’t worry. Here are some possible reasons why the flytrap is not closing and what you can do to solve these problems.

1. Unsuitable Substrate

Regular potting soil cannot be used for Venus flytraps and can poison the plant, stopping its traps from closing. Plant the Venus flytrap in peat, perlite, or sphagnum moss.

One reason flytraps don’t close is that they were planted in the wrong type of substrate like regular potting soil. Most potting soils contain various minerals and fertilizers that could poison the Venus flytrap and slowly cause it to die—preventing it from closing.

Venus flytraps are not like other plants. They require a nutrient-poor substrate, so avoid using these.

Two types of substrate work best for Venus flytraps. One consists of a one-to-one ratio combination of peat with perlite. Another is made with equal parts peat and sphagnum moss.

It’s also important to use the correct pots. Plant pots made of clay or terracotta should not be used. This is because they could contain extra minerals that would leach into the substrate and eventually kill your flytrap.

  >> Discover different planter materials in our article on the best pots for aloe vera!

For a Venus flytrap, the best pot to use would be a planter made of glazed ceramic or plastic. It must also be at least 6 inches deep so the plant’s roots have space for growth.

2. Underwatering

Venus flytraps that are not properly hydrated will not close, making them unable to capture prey. Flytraps need to stay moist and well-watered to grow. Dry and brown traps are signs that the flytrap is being watered enough.

How often you need to water your flytrap will always depend on your environment and its lighting. Rather than give a fixed number to follow, it’s best to check your flytrap and see when it needs water.

Are the leaves starting to dry and turn brown? This could be a sign that the flytrap is underwatered and is too weak to even close its traps.

One of the things you can do is to identify the difference in weight of your potted flytrap before it is watered and after it is watered. Knowing this difference will help let you know when to water the flytrap and when to wait.

Sufficiently watered flytraps will be heavier, while those that are under-watered will be totally dry and extremely light and easy to pick up.

Having said all that, bottom watering is the best for a Venus flytrap. Place the potted flytrap into a tray that is at least 2 inches deep. Then, fill the tray halfway with water.

Once the water in the tray is gone, check the top 2 inches of the substrate of the flytrap to see if it is moist or dry.

Wait until the upper portion of your flytrap’s substrate feels dry before watering it again. This will help you make sure the flytrap is receiving the water it needs.

3. Lack of Distilled Water

Watering Venus flytraps with regular tap water or bottled water can prevent them from closing. The minerals in these types of water could burn the roots of the flytrap and kill it. Instead, use distilled water or rainwater.

It might be convenient to use tap water, river water, or even nearby pond water, but these all have minerals that could burn the roots of your flytrap.

Flytraps require specific types of water to develop normally. Watering a venus flytrap with the wrong type of water, like unfiltered tap water or bottled mineral water, will cause it to slowly die, rendering it unable to close its traps.

Sure, venus flytraps indeed come from poor bogs and swamps. This, however, doesn’t mean it can handle just any type of water.

A flytrap will thrive when the water doesn’t have any minerals mixed in. So use something like distilled water and rainwater.

Reverse osmosis water could be used as well. It sounds a bit complicated but this water is basically just demineralized and deionized water.

You can buy bottles of reverse osmosis water at groceries and a home filter system like this one on Amazon from various online stores.

4. Inadequate Sun Exposure

When a venus flytrap does not get at least 6 hours of direct sunlight, it will weaken and will no longer close properly. If direct sunlight is not available, grow lights can be used indoors.

Unfortunately, some plant growers underestimate the amount of direct sunlight a flytrap needs to grow. What may look right for us could possibly be too much or even too little for these fascinating plants.

Photosynthesis is very important. This is what allows your flytrap to get most of the food it needs to grow. But it can only do this when it is in direct sunlight or under grow lights.

The flytrap needs a minimum of 6 hours of direct exposure to sunlight or a maximum of 12 hours. Any more or less than this will result in a dead flytrap that can’t close up.

Similar to how this plant needs the right kind of water, it also needs to have proper lighting to function. If these basic needs are not met, the plant is less likely to thrive and snap close to consume prey.

5. Overfeeding

Venus flytraps that are overfed will eventually stop closing to preserve their energy. Feed the Venus flytrap once a week and move it to a location with fewer bugs.

Owners of Venus flytraps may feel like these carnivorous plants are their pets. Just as they do with cats and dogs, they may feel the need to give flytraps food—even human food—constantly.

While it may be an easy trap to fall into, this is not a good thing to do!

Flytraps become lazy when full. Once they’re overfed, they will not feel the need to catch more prey and waste their energy.

If you set your flytrap in an area with a large number of insects like flies, it could be eating too much all at once.

   >> Learn more about the 30 Plants That Repel Flies. 

Move the flytrap to a different location to help control this and restrict its feeding to only once a week.

It’s also possible to feed venus flytraps the wrong type of food. Don’t give it human food like chicken, pork, and beef because the flytrap will not be able to digest it. These will rot the leaves and kill your flytrap.

6. Excessive Handling

Venus flytraps that are constantly handled or touched will eventually stop closing their traps. This can cause the trap to go dormant or die so it must be avoided. Refrain from excessively handling the flytrap.

Constant triggering of the traps to close is very tiring for the flytrap. Not only will the flytrap waste energy that’s necessary for growth and development, but it will also become so exhausted that it will no longer close its traps as a result.

It might be cool to own a flytrap but to properly care for it, try to refrain from unnecessary poking.

In some cases, you might need to stimulate the traps to help it snap over its meals. But it’s best to just leave the plant alone.

The flytrap is still a plant with limited energy and it must save its energy to trap its prey.

How Do Venus Flytraps Close Their Traps?

Venus flytraps close their traps when the hairs in their leaves are triggered by the insect. After these hairs are triggered, the plant will send electrochemical signals to the leaves and cause them to close over the prey.

Inside the leaf-like mouth of Venus flytraps, sensory hairs called trichomes can be found. You can see them on the surface and bottom of each leaf. These 3–5 hairs are arranged in a triangular pattern and are easily triggered via touch or pressure.

Instead of using muscles like animals or humans, flytraps use these hairs to sense movement and immediately send signals through the water inside the plant’s cells.

Aside from growing in swampy climates, this could be why it’s so essential to provide flytraps with adequate water.

A Venus Flytrap Works Just Like Your Brain

When an insect is lured into the flytrap by its sweet-smelling nectar, the trap closure will activate after its hairs are triggered. An electrochemical signal is sent to close the leaves immediately, and the prey is trapped in the jaws of the flytrap.

But unless the plant is properly cared for and is given everything it needs, your Venus flytrap might not be able to deliver these signals to close its trap, even if they are on the brink of death.

FAQs

How long does it take a Venus flytrap to close its mouth?

The Venus flytrap can snap shut in half a second or the blink of an eye once it receives the signal to close. The longest time would be about 2 minutes after the initial signal is received.

Are there Venus flytraps that naturally do not close?

There is no such thing as a Venus flytrap that naturally doesn’t close. But other carnivorous plants that do not need to close over their prey. The purple pitcher plant has nectar on the top rim of its leaves to attract prey. Once attracted, the prey will slip down into a digestive liquid and will be absorbed.

Summary of Why Venus Flytraps Do Not Close

Venus flytraps that are planted in an unsuitable substrate, are not getting sufficient water, are watered with the wrong kind of water, are not getting enough sunlight, are overfed, and are excessively handled will not close their traps.

Ensure that Venus flytraps can close up by planting it in 1:1 of peat and moss or 1:1 of peat moss and sphagnum moss in a glazed ceramic or plastic pot. It should also receive direct sunlight for 6–12 hours.

Additionally, the Venus flytrap must be given distilled water or clean rainwater and watered from the bottom once the top 2 inches of the substrate dries up. Only feed the flytrap with insects once a week and don’t handle and poke it unless necessary.

Sources

• “How does the Venus flytrap work?” by n/a in University of Tasmania
• “Venus Flytrap” by the editors of encyclopedia in Britannica
• “Carnivorous plants: the meat-eaters of the plant world” by n/a Natural History Museum
• “Growing Instructions for Venus Flytrap” by Dan Hodgson in North Dakota State University