If you’ve ever admired the extra-large leaves or unusual looks of a monstera plant, you’re not alone. Since the 1960s, this genus of houseplants has been in high demand for decorating in all styles offering a host of uses and benefits. Whilst Monstera plants can live for many years, they are notorious for being a little tricky to keep indoors without practice. If you’re finding brown spots on the glossy leaves of your monstera plants, don’t panic. There are several potential causes, and all of them can be addressed with a bit of care. Brown spots won’t disappear on your monstera plants, but new foliage should be free from discoloration.
Brown Spots on Monstera Plants – The Essentials
The most common causes of brown spots developing on monstera plants include common pests and diseases, inappropriate watering, overexposures to direct sunlight, and issues arising from overfertilizing these plants. Each can be addressed with adjustments to everyday Monstera plant care.
Common Reasons for Brown Spots on Monstera Plants
Explore the most common reasons for brown spots to appear on Monstera species to determine what’s going on with your plants. These are prevalent across all types of Monstera including classic Monstera deliciosa, variegated monstera, and rarer plants such as Monstera obliqua, and Monstera Peru.
1) Pest, Disease, or Bacterial Infections
Multiple pests and fungal diseases can lead to smaller, contained brown spots on Monstera leaves. Scale are brown to black insects that may resemble a raised spot on the leaf but instead are a pest feeding on sap. Fungal leaf spot causes sunken brown spots, as the name suggests.
How To Identify
Look for small, sunken brown spots that appear on the lower leaves first for fungal diseases. Pests like scale will appear as raised, lighter brown spots instead. Scale will peel off with effort, while other brown spots will be part of the leaf and impossible to remove in one piece.
Best Cures and Remedies to Fix
Avoid overwatering the Monstera plant and drop the humidity around the plant if you suspect a fungal infection. Don’t mist the leaves either if brown spots appear. For scale and other insects, try wiping both sides of each leaf with isopropyl alcohol mixed 50/50 with water to stop pests.
2) Root Rot
As the name suggests, root rot involves the rotting of the root tips at the bottom of the pot. This problem can affect Monstera at any stage of growth, usually killing off the leaves from the bottom up. However, brown spots may appear first. These brown spots may be in the center or at the edge of the leaf and may or may not have a sunken, wet appearance.
How To Identify
Check for larger brown spots that appear on older leaves. Carefully lift the plant out of its pot to see if there are any visible signs of rot around the roots. Rotten roots will be darkened, mushy, and may have an unpleasant odor, while healthy roots are white and firm.
Best Cures and Remedies to Fix
You can trim off the damaged root materials. Use a looser, better draining soil mix to repot the plant and watch out for overwatering it moving forward.
3) Underwatering or Very Dry Growing Conditions
While Monstera plants don’t respond well to overwatering, they also struggle if they’re allowed to dry out too well. Don’t go more than two weeks without watering your monstera plant. Water well and soak the potting mix thoroughly, or you may notice lighter colored and crispy brown spots forming on the leaves.
How To Identify
Brown spots caused by a lack of water will be light tan, dry to the touch, and near the edges of the leaves. They may appear on both new and older leaves equally.
Best Cures and Remedies to Fix
Water more regularly, but more importantly, give the plant enough water to soak it thoroughly each time you water. Consider setting the plant in a bucket for watering from the bottom up if possible. Don’t swing to overwatering the plant as a reflex, or you might end up with another type of brown spots.
4) Overwatering or Very Damp Growing Conditions
Monstera plants don’t like the soil around their roots to stay damp or wet for long. If you water them too often, you may see dark and sunken spots appearing on the leaves. The spot itself may be wet or slightly rotten.
How To Identify
If the soil stays damp and doesn’t dry out before you water the plant again, you’re using a soil mix that is too heavy, or you’re watering too often. Aim to water only once every seven to 14 days. Overwatering can lead to root rot, so rule out that problem before assuming just watering less will work.
Best Cures and Remedies to Fix
Try a lighter and better draining soil mix to prevent water from lingering around the roots. Poke your finger in the soil and avoid the urge to water until the top inch to two inches of soil dry out.
5) Sunburn
While Monstera plants want a steady supply of indirect light, they prefer not to receive direct sunlight too often. Unless you slowly introduce a Monstera plant to direct sunlight in small doses (pariculary important for recently propagated Monstera plants), you’ll find that exposure leads to sunburn in the front of browning on the leaves.
How To Identify
Browning caused by sunburn can be in the form of a spot or circle, but it’s just as likely to be an entire edge of a leaf or an irregular shape. This damage will be a medium to light brown and dry to the touch. It may lead to the entire leaf turning yellow and drying up relatively shortly after exposure, depending on the amount of damage.
Best Cures and Remedies to Fix
Prevent further sunburn by moving the plant away from sunlight and trimming off any damaged leaves. Watch for how the angle of the sun changes between seasons and try moving the plant away from the windows when summer arrives each year. For more, see our in-depth guide on the best places to position Monstera plants in the home.
6) Lack of Light
Keeping Monstera in the dark doesn’t work well. The leaves tend to lose color and turn yellow, but they may also develop scattered dark spots. These brown spots may have no other apparent cause and tend to appear on older leaves.
How To Identify
Try moving the Monstera into an area with brighter light or adding a plant light to supplement it. If the brown spots lighten but don’t disappear, the problem was likely a lack of light.
Best Cures and Remedies to Fix
Make sure to supply your monstera plant with at least four to six hours of light, keeping it indirect at all times. A plant light is the easiest way to achieve this goal in most homes.
7) Over or Under Fertilizing
As a plant with medium feeding requirements, Monstera plants need a half-strength dose of fertilizer once a month during the growing season. However, the overuse of fertilizer can burn the leaves and lead to brown tips or splotches along the center of each leaf.
How To Identify
Brown spots that appear on new foliage after fertilization indicate an issue with over-fertilization. If nothing else about the plant’s health has changed recently, fertilizer application or the lack thereof is always a potential culprit.
Best Cures and Remedies to Fix
If the brown spots are due to a lack of fertilization, try applying a quarter or half-strength dose of a product like Miracle-Gro for Houseplants. Over application is harder to fix, with repotting in a fresh monstera soil mix being the best approach in serious cases.
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Do Some Brown Spots Naturally Occur on Monstera Plants?
While Monstera plant leaves age and eventually turn brown to drop off, the browning rarely appears as spots first. Brown spots tend to indicate an issue with the plant’s care rather than just the inevitable loss of leaves over time. It’s usually fine to leave leaves in place once brown spots have appeared as long as you’ve addressed the underlying cause.
Growing Happy, Healthy Monstera Plants at Home
Depending on the species and variety, Monstera plants require warm temperatures above 50 degrees F to grow. They can’t handle anything below 40 degrees F and prefer higher than average humidity.
Loose and well-draining soil are a must-have for these plants. Dense and water-holding soils will only result in root rot.
While Monstera plants need plenty of light each day to reach their maximum size, they don’t like direct sunlight and may develop sunburn. Keep the light filtered or indirect for glossy growth.
Give them a dose of fertilizer at half-strength about once a month during the warm months of the year, especially if they’re outdoors.
Pruning allows you to control the final height and encourages new foliage to form where you want it. Try setting up a burlap-covered post for the Monstera to vine on, which may allow it to flower or even form an edible fruit.
It’s also prudent to wear gloves when handling Monstera plants as they are considered toxic to humans and pets.
Brown Spots on Monstera Plants FAQs:
Should I cut brown spots off monstera?
It’s prudent to prune or trim any foliage on your monstera plant that appears to be decaying or diseased in any way which will improve the overall health and appearance of your plant.
How do you get rid of dark spots on monstera?
The trick to removing dark spots from new monstera growth is to provide your plant with optimal growing conditions moving forward. Be particularly considerate of light exposure and watering cycles. Existing brown spots can’t be removed directly but should giveaway to healthy, green, glossy growth in due course.
Why are my leaves getting brown spots?
The most common causes of brown spots developing on monstera plants include common pests and diseases, inappropriate watering, overexposures to direct sunlight, and issues arising from overfertilizing these plants.
How do you know if your monstera is overwatered?
Brown spots, yellowing leaves, laggy growth, and bloating or drooping of the plant are common signs that you are overwatering your monstera plant.
Managing Brown Spots on Your Monstera Plants
Monstera plants shouldn’t develop brown spots on leaves, even if some browning is inevitable on the oldest leaves as they dry up. Keep these symbolic plants healthy and happy by avoiding the perils of over and under watering in particular. Choose a good soil mix and apply fertilizer with caution to see good growth and fewer discoloration issues.
If you’re looking for your next Monstera plant to add to your collection, see our in-depth guide to the best plant shops delivering Monsteras nationwide.
Andrew is the Editorial Director at Petal Republic. He holds a BSc degree in Plant Sciences and has trained professionally at leading floristry schools in London and Paris. In amongst overseeing a global editorial team, Andrew's a passionate content creator around all things flowers, floral design, gardening, and houseplants.
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