Uncovering The Mystery Of Brown Spots On Monstera: Causes, Treatment, and Prevention

Brown Spots On Monstera

One of my favourite things about Monstera plants is the large, exotic looking leaves. These plants are prized for their lush foliage and can be quite the striking addition to any room. However, these plants can experience issues like leaf spots, which not only detract from their appearance but can also indicate underlying issues with their health and care. Leaf and stem spots on Monstera can be caused by a variety of issues, such as pests, disease, or improper care. Properly identifying the issue is key to providing your plant with what it needs to recover and produce new, healthy leaves.

Brown Spots On Monstera Stem

Although not as noticeable as spots on the large Monstera leaves, brown spots on the stem of your plant may be equal cause for concern. Inspecting your plant regularly during watering can help you notice issues like this early on, to prevent them from progressing further and causing serious damage to the rest of your plant.

Brown Spots On Monstera Stem

1. Stem Rot

Root rot in Monstera plants is often caused by overwatering or allowing the plant to sit in standing water. Without proper access to oxygen, the roots starve and begin to rot. Eventually, this rotting will progress up your plant to the stems, weakening the base of the plant and causing soft, brown spots to appear.

To treat stem and root rot, remove your plant from the pot it is in and carefully brush off soil. Cut any soft, brown, or mushy roots and stems and repot into clean, suitable dry soil for Monstera plants. Water your plant only when the top few inches of soil are dry, and ensure excess water can drain out of the pot.

2. Dehydration

On the other side of the spectrum is underwatering, causing dehydration in your plant. When your plant is underwatered, brown spots may appear on the stem and leaves as your plant slowly allows tissue to die off in order to reduce the need for water.

To prevent this, water your plant throughly about once a week when the top few inches of soil are fully dry. Make sure your Monstera is in a suitable pot for its size, to ensure enough soil is present to hold and provide water to the roots.


3. Scale infestation

A large infestation of scale bugs may also cause brown spots on the stem of your plant. If you have tiny brown spots on Monstera stems, it is probably due to scale bugs. These small pests will suck the sap from your plant, often starting lower on the stem and eventually moving up to the leaves, leaving small brown spots behind.

Treat these pets by washing the stem and spraying it with a diluted neem oil mixture. This will coat the bugs and eventually kill them off.

Scale infestation

Brown Spots on Monstera Leaves

1. Overwatering

Overwatering is probably the most common cause of brown spots on Monstera leaves. Providing too much water to your plant will cause the roots, stems, and eventually the leaves to rot and go brown, as the plant can no longer get the nutrients it needs to survive.

Follow the tips mentioned above to properly water your plant, and consider repotting your Monstera into a new pot if you suspect root rot due to wet soil, often detected by a strong smell coming from the pot your plant is in.


2. Low Humidity

Low humidity may also cause Monstera leaves to dry out and develop brown leaf spots. Regularly misting your plant or providing it with a humidifier may help to prevent this issue. Keeping your plant around other plants or in a green house will also help to increase the humidity in the air, preventing it from drying out.

3. Sunburn

Monstera like bright, sunny locations, but can be burned by too much sun exposure. This is especially possible if your plant is near a window that gets direct sunlight through it. Sunburned spots on your leaves will be brown and dry, brittle, and possibly break open creating holes.

You can remove sunburnt leaves from your plant by carefully pruning them off at the bottom of the stalk. Leaves that have been burnt will not fully repair the damage, so it is better to give your plant a chance to fully replace the leaf with a healthy one. If many leaves are damaged, remove only a few at a time to avoid over-stressing your plant.


4. Pests and Disease

There are also pests and disease, like fungal leaf spot, that will cause dark spots on Monstera leaves. Pests and diseases can be hard to identify, so inspect your plant closely for any signs that might help you identify the cause.

To prevent pests and disease, keep your plant healthy with regular fertilizer and proper care. Pests can often be treated and prevented with frequent applications of a herbicide spray or neem oil diluted in water. Prevent the spread of disease in your plant by removing affected leaves and stems by carefully cutting them off with a clean pair of garden shears.

Closing Tips

Pests, disease, sun damage, improper humidity, and both over and under watering of your Monstera may cause unsightly brown spots to appear. Taking quick action to identify the issue and provide treatment can help to get your prized plant back on track, and allow it to thrive once more!

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