This Is Why Your Monstera Deliciosa Looks Burnt

There are a variety of reasons that your Monstera looks like its leaves have been burnt.

If you’re Monster doesn’t look burnt, but does have brown or black spots on the leaves, check out this article.

So, why does your Monstera look burnt?

It is burnt

I mean, it can happen, and pretty easily.

Contrary to popular belief, Monstera can tolerate very bright, direct light IF (and it’s a big if) they’re acclimated properly.

When plants are exposed to bright light, they can produce more of a compound called carotenoid, which protects them from sun damage.

Unfortunately, they can’t produce them quickly without warning, which is why shifting your Monstera from the cupboard under the stairs to the south-facing french doors will result in very dead foliage very quickly.

(The plant won’t be dead though, in fact the roots like the warmth, so long as the soil is boiled dry)

I have an article here on what to do if your Monstera is sunburned, but you can 100% just chop off all the brown foliage and it’ll regrow.

If you keep it outside it can grow back quickly and with leaves that won’t burn as easily, but it will need a LOT more water.

When my Monstera are outside I check the soil daily because the additional heat, speed of growth, and air movement can make them dry out super quickly.

Pest damage can make Monstera leaves look burnt

Thrips are just part and parcel of Monstera care – they’re usually not an issue if you keep on top of washing your plant leaves.

They absolutely can move to other plants, but they like Monstera so if you keep the population low, they usually stick to the one plant.

Thrips operate by sucking the juices out the plant leaf, and effectively killing it. It starts off brown but then can go black over time and can result in the leaf looking burnt.

Thrips are big enough to see, but the larva are smaller and the eggs are laid inside the leaf so the damage they cause may be your first clue that they’re there.

You also might see smaller black dots. This is thrips poop, and you can wipe it off with a damp cloth.

thrips damage brown spot on Monstera

Cold shock can make Monstera leaves look burnt

If your plant is exposed to a cold blast, or accidentally left outside in the cold, the resulting black marks can look very much like a burn.

Not only do you get black marks, but they may have a yellow/orange outline that also looks a bit burn-y.

When plants get too cold, the cells in the leaves freeze and expand. The cell walls break and the tissue dies. It can look burnt because the dead tissue still has liquid in it, so it’s black rather than the ‘traditional’ brown colour of dead leaf.

Overwatering can make leaves look burnt

Overwatering damage looks burnt for the same reason – the plant tissue is dead, but because there’s so much excess water in the cells, it looks black and burnt.

Monstera are more forgiving of overwatering than many other topical plants, but if you keep the soil consistently wet then it can happen.

I have an article here on how to save an overwatered Monstera, but removing any dead, brown, or mushy roots, washing the remaining roots in hydrogen peroxide is the short version. Repot in fresh soil, and only water your Monstera when the soil is dry (or reading a 2 on the moisture meter).

black monstera leaf

Underwatering can make leaves look burnt

Underwatered leaves tend to look more brown and crispy rather than black but it can still sometimes look burnt.

I get people insisting that they water their Monstera regularly, but it’s still showing signs of being underwatered. This can happen for a couple of reasons:

  1. The soil has become hydrophobic
  2. The plant is rootbound

Hydrophobic soil occurs when the plant gets so dry that the soil compacts into a solid lump. Water always follows the path of least resistance, so it’s run through the gap between the soil and the pot.

It can also happen when the soil doesn’t have enough chunks in it, so adding orchid bark or LECA can really help. Soil also compacts over time, so it might be time for a repot.

If the soil is ok, but you’ve let it get too dry, then you can rehydrate soil by soaking it from the bottom up. Just set it in a bowl of water* and leave it until the top of the soil is damp.

*Don’t add fertiliser at this point – dried out roots won’t be able to absorb it properly and it can burn them and damage them further.

Spraying with pesticides can burn plants

I got thrips on my Monstera peru (not a Monstera by the way, but I thought i’d mention it). I sprayed it with a very strong solution of soap and water (you should use a drop, but this was a full on drizzle) and now I have this situation:

Whoops.

Don’t do what I did to get rid of thrips.

If this has all been a bit overwhelming, and you’re new to Monstera deliciosa, this article might help you get your bearings.

Caroline Cocker

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

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