This Is Why Your Monstera Leaves Are Getting Smaller

This post may contain affiliate links. Read the full disclosure here.

So it’s common knowledge that in order for your Monstera deliciosa to get big, beautiful fenestrated leaves like these:

monstera with lots of holes in the leaves

…you need a lot of light and a lot of patience.

But what if we don’t want to wait? What if we’d rather chuck money at the issue and buy a Monstera that’s already super mature?

We don’t have time to mature our own Monstera! We’re hacking the system!

So we go out and buy a Monstera with massive leaves and a stem as thick as our arm, and then the next leaf it throws out looks like this:

immature monstera leaf
You see, whilst it's true that Monstera need time to get fenestrations, other factors are just as, if not more important. 

A monstera only produces leaves with fenestration if it needs to.

There’s no point growing big, beautiful leaves if the conditions aren’t right.

May as well save some energy and grow some shitty little ones!

Here are some of the reasons that your previously awesome Monstera has reverted to growing only rubbish leaves:

It needs time to settle in

Being moved around a lot is pretty alien to a Monstera. Plants, by their very nature, don’t move very much.

This will typically cause the newest leaf to be either formed improperly (so it'll only form a half leaf, and the bottom will brown off and shrivel up) or the leaf will be whole but...weird. 

Like deformed or weirdly curly or something.

On occasion, shock can cause the next leaf on a Monstera to be immature and a bit stunted. If the next leaf is fine, you can attribute it to shock, but if the following leaf is just as disappointing, your Monstera may be after something else.

It’s getting less light than it has done previously

Light is the major influence over Monstera producing fenestrated leaves.

It’s often stated that Monstera need bright, indirect light, but trust me, they can tolerate bright direct light in a LOT of places.

My Monstera (including my variegated one) live in a south-facing window that takes up one wall of the living room and they don't burn. 

You do need to acclimate them, but they can definitely handle it here in the UK.

You probably bought it from a garden centre with extremely bright light, so put it somewhere where it will get a similar amount to minimise the chance of the leaves reverting to their immature form.

If you don’t have bright enough light, you can try grow lights, but you’ll need professional ones to get mature leaves.

Anything with just a USB connection likely won’t be powerful enough.

For those of you that have Monstera that are producing smaller leaves but the light hasn’t changed, then make sure that you’re keeping the leaves clean. This will help the Monstera maximise photosynthesis and therefore grow faster.

There are also other things that can influence the light, such as the time of year or the cleanliness of your windows.

It’s surprising how much less light can come through a dirty window in winter compared to a clean window in summer.

It needs repotting

Monstera like to be snug in their pots, but only up to a point.

if you find yourself having to water your Monstera several times a week, or when you take the plant out of the pot you can’t see any soil, it’s definitely time to repot.

Don’t go up too big of a pot size. Monstera like to feel snug in their pot, and if they don’t they’ll work on remedying that rather than growing leaves. A couple of inches is fine.

It needs staking up

Luckily, Monstera haven’t actually realised they’re being kept in our house rather than in the rainforest. Therefore, we can trick them into producing bigger leaves by growing them up something.

Don't overthink the moss pole thing. 

There are advantages and disadvantages to the different types, but the most important thing is to get it growing up. 

A sphagnum pole is great because it can grow a secondary root system in the pole, but if all you have is a coir pole it can grow just as big, you’ll just need to repot more often.

Don’t bother trying to get the aerial roots to attach to the coir, just tie the stem (not the petioles) to the pole with garden ties.

It needs fresh potting mix

If it's been a few years since you repotted your Monstera (this is surprisingly common, especially if your plant is huge) then you might be due a soil switch. 

Whilst there’s no specific timeline to follow for doing a total soil switch, it can be a good idea if your plant has been in the same substrate for a significant amount of time.

Whilst the pot size might be fine, it might be time to add some fresh potting mix.

It has pests

Check for pests. They’re usually pretty easy to see on Monstera – check around the veining on the backs and fronts of the leaves for thrips larvae – also the bit of the petiole that housed the next leaf:

petiole crotch

Thrips love to hang out in the petiole crotch (not the botanical name), as do mealybugs. I turn my spray bottle nozzle so it emits a nice solid arc of soapy water and blast those buggers out.

As well as producing immature leaves, pest-infested Monstera are likely to produce deformed, stunted leaves, and those weird half-leave where it looks like the plant gave up halfway through, like this Anthurium leaf:

deformed anthurium leaf

It’s fine, pests happen.

Once the pests are gone (that sentence is doing a lot of heavy lifting lol), your leaves *should* return to their mature form pretty soon.

It needs feeding/fertilising

I’ve seen Monstera described as being both heavy and light feeders.

I personally fertilise mine a lot (like, every time or every other time I water), because I find it helps them grow faster, and with fast growth comes fenestrated leaves. 

I think the reason people say they’re light feeders is because if you don’t fertilise often they don’t really suffer, they just don’t grow as big or as quickly.

Final thoughts

The most likely reason that your Monstera is putting out smaller leaves is that it’s getting less light than it was when it produced the fenestrated leaves.

There are certainly other factors that come into play, but repotting your Monstera, or changing the soil won’t help produce fenestrated leaves unless the light is bright enough.

Just because your Monstera has produced fenestrated leaves in the past doesn’t mean it will continue to do so regardless of its environment. Those fenestrations serve a purpose, and if they’re not needed, they won’t grow.

Caroline Cocker

Caroline is the founder and writer (and plant keeper) of Planet Houseplant

Leave a comment