When Do Monstera Leaves Split? (+ 3 Tricks To Encourage Them To Split)

If you have a Monstera plant, you may be wondering when it develops those amazing leaves with holes in them. Monstera plants are known for their extraordinary and extremely beautiful foliage, but in young plants, the leaves are full and have no holes. So, when do Monstera leaves actually split?

Monstera leaves split when the plant reaches about two or three years old, and rarely before this. However, if your Monstera plant does not seem to be splitting its leaves, there are a few things you can do – and don’t worry, because this doesn’t mean that the plant is sick. With a bit of patience and perhaps some extra care, it will soon sport those iconic leaves.

When Do Monstera Leaves Split?

Although all plants are individuals and will have different rates of growth, your Monstera plant’s leaves will usually start to split when the plant is about two or three years old. Before this, it will have the same heart-shaped leaves, but they will not have the recognizable splits and holes in them.

Most people are very keen to see these holes develop, and will watch their Monsteras eagerly for the first sign of them. If you are frustrated with waiting for your Monstera to start looking like a proper, adult Monstera, read on to find out more about splitting leaves and how to encourage them.

Remember, that patience is a virtue, and many plants are slow to change. Most will take their time, and will not be rushed.

What Are The Holes In The Leaves Called?

Even if you are a big fan of Monstera plants and their amazing leaves, you may not be aware that the practice of making holes in the leaves has a special name – leaf fenestration. Monstera plants are not unique in using this technique, although they are unusual, and they are probably the most famous example of it.

Leaf fenestration

Other plants that use leaf fenestration to their advantage include Lithops and Haworthias.

Why Do Monstera Leaves Split?

You might be wondering why these plants grow splits and holes in their leaves in the first place. After all, this is quite an unusual look and not many plants do it – which is partly why Monstera plants are so well-loved and so sought after.

There are quite a few reasons that these splits could prove an evolutionary advantage to a Monstera plant – so let’s look at what those are. It should be noted that these are mostly speculation, as nobody has actually proven why these plants grow the way they do. It may be for several of these reasons combined.

Reason One) More Water Can Access The Roots

Monstera plants do have subterranean roots in the soil, but by the time these plants are adults and growing at significant heights, these roots represent quite a minimal part of the plant. Monsteras also have aerial roots, which are mostly in contact with tree trunks and the air.

By allowing water to pass through the leaves, more water gets to these aerial roots, because they are not sheltered by waterproof leaves. This may allow the Monstera to collect more water, and as it likes to be kept damp, this is a feasible explanation.

However, the air in rainforests tends to be quite wet anyway, so it is not clear that this offers major advantages – although it may help a little.

Reason Two) It Helps Them Withstand Winds

Growing at a height, as mature Monstera plants do, can mean that they are vulnerable to strong winds in the upper parts of the rainforest. By creating slits and holes in their leaves, they make themselves far less wind resistant.

This means that when strong winds whip up and around them, they are not buffeted so severely. In turn, this reduces the risk of leaves snapping off the stem, or even pulling the whole plant down.

The wind can pass through the leaves, massively reducing the strain put on a plant in stormy weather. Other plants use this technique, and since Monstera plants have big leaves, this seems a reasonable evolutionary choice to reduce their wind resistance.

However, many plants do grow at heights in the rainforest without this, so again, this explanation is not wholly satisfying. It is certainly plausible, but there may be more to it than that.

Reason Three) It Makes Light Use More Efficient

This is probably the most compelling theory at present because it makes the most sense. In the rainforest, light is in very short supply, and it is also something that all plants are desperately aiming to maximize their contact with.

Monstera plants grow in a long, relatively straight line as they scramble up tree trunks toward the canopy. If their upper leaves block out too much light, their lower leaves do not serve any purpose, and instead, just waste energy.

Monstera Climbing a tree

However, the Monstera does need to have lots of leaves, because the light patterns in a rainforest are constantly shifting, and the more coverage it has, the better. Developing leaf fenestration allows the plant to spread its leaves over a wider area. Some tiny amounts of sun may get through them and be picked up by leaves lower down.

In scattered light, a Monstera has an advantage because it can cover multiple different heights with lots of big, broad, sun-catching leaves, but it still ensures that its lower leaves get light and serve a purpose. 

It, therefore, seems quite likely that the Monstera has developed leaf fenestration as a technique to maximize the light it can collect. Nevertheless, the other two factors may partially explain the fenestration technique, or may at least be additional advantages that the plant enjoys as a result of it.

Which Leaves On A Monstera Plant Will Split?

When your Monstera’s leaves start splitting, this will usually only happen on new growth. Leaves that were already on the plant when it starts to develop this technique will remain whole, and you may wish to remove these once the holey foliage is established.

They will die and drop off eventually on their own, but if you have been waiting eagerly for the split leaves, there is no harm in removing the old ones, provided that the plant is healthy and has developed enough other foliage to survive and photosynthesize effectively.

What If My Monstera’s Leaves Do Not Split?

If your Monstera plant’s leaves do not seem to be splitting, you might be wondering what to do and what’s going wrong. The answer is probably that your plant simply isn’t old enough yet. 

Young Monstera Plant

Although most plants will have started to develop leaf fenestration as a technique by the time they are three years old and around three feet tall, this is not a hard rule that all Monstera plants abide by.

Provided that the plant seems healthy and it is continuing to grow, don’t panic over the lack of holes in the leaves. Given a bit more time, your plant will probably start producing them. 

However, if you are desperate to see this process starting and your plant is still not showing any signs of splitting leaves, you might be wondering what you can do to encourage them. We will cover that next.

How Can I Encourage My Plant’s Leaves To Split?

So, if your Monstera seems stubbornly un-holey, what can you do about it?

There are a few tricks you can try, which we are going to explore, but note that if your plant isn’t old enough, none of these will work.

Trick One) Remove The Old Leaves

As mentioned above, you do not need to leave the unsplit leaves on the plant when it has started to develop leaves with holes in them. Indeed, once your plant has enough of these leaves to sustain itself, it may actually be better to remove the old ones.

This encourages the plant to produce more foliage (because it realizes that it does not have enough), and this foliage will be split. It also gives the plant more energy to put into new leaves, rather than trying to sustain the old ones.

Altogether, this is a great way to help your plant grow more leaves with holes, but can you encourage it to start doing so if it hasn’t yet?

Trick Two) Provide More Light

Some people say that if you give your plant more light, it will split its leaves more readily. This makes sense if it is true that the splits are designed to let the light fall onto foliage beneath because more light from above would prompt this.

Montera Deliciosa behind curtins

Do not suddenly increase the light that your Monstera is exposed. While these plants do enjoy light, they are rainforest plants and they will not handle being moved into a huge amount of bright light.

Monsteras do not like strong, direct sunlight. They often do better in bright but indirect light. You can achieve this by positioning them near a window, but out of the sun’s rays. Alternatively, put them closer to the window but put up a sheer curtain or something similar to screen some of the light off.

Remember, these plants grow beneath the canopies in rainforests, so although they enjoy sunlight, they have not evolved to tolerate it in great concentrations. Light is good, but take the time to get this balance right and ensure your Monstera is neither burning nor dying in the dark.

Trick Three) Meet Its Needs

A happy and healthy Monstera will grow as it should – and that includes leaf fenestration. If your Monstera is sick or lacking in vital nutrients, it is less likely to grow in the normal way, and that means its leaves may not split as you would expect them to.

There are a few things that you need to do to keep your plant healthy:

  • Water – done regularly enough to keep the plant damp without causing root rot or fungal infections.
  • Humidity – Monsteras like humidity levels of 40% and up, as this keeps the foliage clean and fresh, and more likely to behave as it should.

Remember, a healthy Monstera that has as much light, water, food, and humidity as it needs will grow holey leaves as soon as it is old enough and large enough. Don’t expect it to start before it gets big, though!

How Often Do New Leaves Grow?

This depends on how healthy your plant is, how much access it has to the resources it needs, and how old it is. Mature Monstera plants grow more leaves, but in the early years, your Monstera will probably develop one new leaf every month or two.

The plant should also continue to grow both horizontally and vertically, widening its spread and reaching higher. Some Monstera plants grow up to eight feet tall, so be prepared for this if you have one!

The leaves should also increase in size steadily, and some can get to around eighteen inches across. It can be fun to measure them and see what the largest is on your plant.

If your Monstera seems to be growing very slowly, you should try and run through its list of basic needs. Does it have enough light, food, water, and humidity? Is it falling into shade for most of the day?

Try topping up its fertilizer, moving the plant a bit closer to the window, or installing a grow light to give it a boost, especially in the winter months.

Conclusion

Monstera leaves will not split until the plant is around two or three years old. It must also be large enough for there to be an advantage to splitting its leaves. When it is young, the lower foliage is not blocked from the light by the upper foliage, so these splits are not necessary.