Few indoor plants are as beloved as the monstera. Prized for their hole-covered leaves, these enormous plants can add tropical tranquility to any space. If you own one, you might wonder what exactly causes these holes (known as leaf fenestration) to occur.
A prominent theory as to why monstera leaves have holes is that the holes help sunlight and water reach the lower parts of the plant. Though, some debate that they exist more to reduce the force of strong winds and help with cooling the leaves.
Below, we get to the root of why monstera plants grow splits and holes in their leaves. Along the way, you’ll learn how leaf fenestration occurs and what you can do to encourage it in your plants. So, let’s dive in!
Why Monstera Leaves Have Holes
Monstera Deliciosa, or just monstera for short, is also known as the “swiss cheese plant.” The moniker comes from the fenestration of the plant’s leaves, which causes holes and splits to occur.
Unfortunately, botanists don’t agree on the reason why the plant grows these unique features.
There are a few theories, though. Some claim that the holes facilitate the passage of water and sunlight, while others contend it has more to do with wind.
Below are some of the top ideas on why monstera leaves have holes.
Protection Against Strong Wind
One leading idea is that holey leaves benefit from the free passage of air through them.
Strong winds can be damaging to vulnerable plants. Leaves may be torn up and stems wholly snapped off.
This is especially important for the monstera for two reasons:
- The plant’s original habitat is prone to storms. Monstera plants come from Central America, which experiences frequent tropical storms and hurricanes. As a result, resistance to gusts is invaluable.
- Broad leaves are vulnerable to the wind. While the plant’s enormous leaves are part of the reason they’re prized, it’s also a weakness. The large surface area means they could catch strong winds if they lacked holes, much like an umbrella.
These holes could also help the plant keep cool by letting breezes pass through them. A crucial adaptation in the hot and humid jungles they originate from.
Passage of Sunlight and Water
Another belief among researchers is that fenestration helps light and water reach the lower parts of the plants.
Monstera plants are a type of epiphyte, meaning that, in nature, these organisms grow almost exclusively on other plants. As a result, monstera grows aerial roots, which are essentially roots above ground.
Since their roots are above ground, the plant wants to ensure water reaches them.
Here’s where leaf fenestration comes into play.
Holes and splits allow rain to fall through the monstera’s leaves. The plant’s aerial roots can then absorb it.
Furthermore, monstera leaves become massive. Without the holes, the weight of collected water could cause the stems to snap off.
Similar to water, light can also pass through the holes and splits—an especially crucial adaptation when you remember these plants grow with scant sunlight under the canopies of trees.
Defense Against Herbivores
Another less prevalent theory is that leaf fenestration is actually a defense mechanism against animals.
But how does that work, you might ask?
Well, there are two possibilities:
- Holes make the leaves look less appetizing. Some believe the plant’s fenestration makes it less appealing to herbivores. Animals may instinctively think the leaves offer fewer nutrients or are diseased.
- Fenestration provides camouflage. Less visible surface area makes the plant harder to notice, especially among other leafy flora. Holes and splits could also allow animals to see something more appetizing behind a monstera.
Of all theories, this one suggesting that fenestration is a defense against animals seems to hold the least water. That’s mainly because fenestration increases over time, even though young plants would benefit most from the adaptation.
Are Holes Bad for Your Monstera Plant?
Those new to owning a monstera often worry about the fenestration, especially in older plants where the holes and splits become quite noticeable.
After all, these marks would be a sign of disease for most greenery.
Fenestration is completely normal for monstera plants. And as they get older, these holes and splits ordinarily become more common. Thankfully, you don’t need to worry.
However, there are some other signs that your plant might need some tender love and care.
Other Common Issues for Monstera Plants
Here are some potential problems to look out for and what they usually mean for your plant:
- Browning leaves. This is caused by underwatering or overwatering.
- Leaves are not splitting. The plant is too young or needs more sunlight.
- Yellowing leaves. Often due to overwatering but can occur naturally. Trim as needed.
- Curling leaves. Excessive heat and low humidity cause curling.
- Rotting roots. Usually caused by too much moisture on the roots. It can also be due to fungus.
The broad holey leaves and aerial roots of the plant also make them appealing to insects. If you notice that your struggling plant isn’t improving despite your efforts, try checking for bugs.
Creepy crawlies are excellent at hiding on your plant and they contribute to the issues listed above. You can typically get rid of them by hosing your plant, applying pesticides, or even using home remedies.
How To Increase Monstera Fenestration
Now that you know that leaf fenestration isn’t bad, you might want to see more of it! But how do you encourage more holes and splits to appear on your monstera’s leaves?
As it turns out, the process is pretty straightforward.
The easiest way to grow more fenestration is by giving your plant more light. So if you keep yours in a darker area, try moving it closer to a window. It can also help if you place the plant directly in light for limited periods of time.
Here’s a YouTube video on how your monstera can get more ferestrations:
Just make sure your monstera doesn’t get too much sunlight. Excess light can cause foliage to appear scorched and die off over time.
Another way to boost fenestration is by trimming smaller, older leaves. Doing so will allow new leaves to grow bigger, facilitating more dramatic holes and splits.
The reason why holes appear on monstera leaves isn’t fully understood, but there are several theories. In any case, fenestration gives their foliage a unique tropical vibe that plant lovers adore.