Why Are There Yellow Spots on Monstera Leaves?

Monstera is a beautiful plant that has large, heart-shaped, shiny leaves. But, the beautiful leaves are susceptible to being damaged by unsightly, irritable yellow spots from time to time. The presence of yellow spots on leaves is an indication that you’re an experienced gardener!

Fungal diseases like septoria leaf spot monstera leaf blight powdery mildew, rust and anthracnose are among the most frequent cause of spots that appear yellow on the leaves of monstera. Apply fungicides to get rid of fungal spores. Place the plant in a cool, well-ventilated location and let the soil dry between irrigations.

Don your detective hat because I’ll assist you in determining the cause of your Monstera.

What Causes Yellow Spots on Monstera Leaves

[1] Improper Watering

The most frequent reason for yellow spots on the leaves of monstera is the lack of water. Monstera leaves change color or are flecked with yellow spots when exposed excessive or insufficient water.

They could also be a sign of excessively humid conditions, which can cause fungal leaf spot disease.

Incorrect watering and deficiencies in nutrient levels often coexist. This is particularly relevant for magnesium, iron and nitrogen deficiency. This is because the moisture in your soil affects the ability of your monstera to absorb nutrients.

I’ve created a table to make it easier to distinguish between an underwatered and overwatered monstera.

You can observe that the majority of the symptoms associated with excessive and insufficient water have a lot in common. If your plant has spots of yellow on the leaves The first thing to be looking for is an alteration in the growth medium. Place your index finger in the soil.

  • Are you wet all the way?
  • Are you able to tell if it is soggy or mushy?
  • Do you smell rotten coming from your soil?

The problem with underwatering your beasta is more troublesome that overwatering the plant. The yellowing of the older or lower foliage is the initial sign to show up. Root rot is most likely to have affected the plant as it starts to lose its shape and then develop yellow spots.

Crispy yellow or brown leaf tips as well as edges can be the initial indicators of the dehydration. New growths are also among the first to be affected by submersion. The leaves eventually will wilt then die and disappear.

Other issues with watering that could result in yellow patches on the leaves of monstera are water splashing, wetting leaves as well as overhead watering. Similar to the watering of your monstera using tap water.

Solution

The fix for a thirsty beast is simple:

  • It must be soaked in water and thoroughly
  • Be sure to keep your plant watered until the excess liquid spills from the drain holes at the bottom.
  • If the pot is a bit rusty and you want to let it absorb the water from the bottom of a tub or sink that is filled with water. Let it drain the excess water completely prior to putting it back.
  • To prevent drowning, make sure to water the area every two to three weeks. Give two inches of the soil to dry out between irrigations.

monstera two leaves

Reviving a monstera that has been overwatered is much more difficult. The most effective course of action will depend on the presence of root rot and the severity. If the monstera roots are healthy, let the growth medium dry and you’ll be good to go.

If you’ve noticed that root rot has taken over on your plant tree, then repotting it is an excellent option. Here’s how:

  • The first step is to trim away any diseased, dead, or heavily affected areas.
  • Remove your monstera from the pot and cut off black or rusty brown roots that are mushy. The result should be with white, bouncy roots in the ball of root.
  • Make sure to treat your flora with fungicide prior to repotting it with a fresh mix of growth medium. Add hydrogen peroxide to the mix to ensure better sanitation. I also add coconut coir, perlite, or lava rocks for better drainage and aeration.
  • Provide the right conditions for growth to speed up recovery

It is important to note that monstera is extremely sensitive to chemical deposits that are typically found in tap water from cities. Therefore, it is recommended to make use of distilled or filtered water. Rainwater is another option that’s worth considering.

[2] Bacterial Leaf Spot

Leaf spots caused by Bacterials are the most frequent in Monsteras that are overwatered or stressed.

Anything of the Xanthomonas and Pseudomonas bacteria could cause it. The illness can manifest in many different ways.

Halos of yellow and dark brown are among the most frequent signs.

When you look at the leaf, it might be able to see some light or dark dead spots. Spots with black edges are common in the presence of severe infections.

Bacterial leaf spots are typically irregular in appearance and may extend to as large as one-half inch in size.

They may be visible on the undersides of leaves as well as on the tops of the leaves. The sticky substance could be released from these areas.

Brownish or yellow spots can be typically found near the edges and tips of the edges of the. They may dry out and remove leaf tissue.

The leaves are fragile and thin or even papery due to this process. If the infection is serious enough, it can cause the plant to die.

Treatment

  • Get rid of and isolate your monstera as soon as you see the bacterial leaf spot.
  • The best way to prevent it is through prevention. It all boils down to proper sanitation. Get rid of fallen leaves and plant waste
  • The few treatments that you have to use be effective in the stage of the illness. This includes the use of copper fungicides and bactericides.

[3] Monstera Leaf Blight

Leaf Blight is a fungal illness that is a threat to monsteras living in moist, warm environments. The fungal spore is able to survive within fallen leaf litter or in other objects. The majority of the time, it infects your monstera via irrigation water.

The leaf blight can be seen on the foliage close to where the soil lines.

This is particularly noticeable when your plant is overwatered. Lower (older) leaves develop dark brown spots that are surrounded with yellow rings. In the end, those yellow dots on the leaves of monstera look like target rings.

As the fungal infection advances, the leaves become brown, curl and eventually die. The plants known as monstera that have the longest and newest are the most vulnerable to leaf blight.

Control and Treatment

The most effective method to control the monstera leaf blight is to address it as quickly as you can. If you spot the appearance of blight on your leaf, apply a fungicide that is labeled as a leaf blight fungicide.

I suggest sprays that can be taken with you wherever you go, such as mancozeb, Anilazine and copper Octanoate (Check the most recent price on Amazon right here).

Changes in culture are also beneficial:

  • Do not work with or handle the wet monsteras
  • Cleanse your garden clothes and cutting tools
  • Beware of overwatering, splashing water, and overhead irrigation

Bag, remove, and dispose of infected components as well as plants. Be sure to do this prior to. winter.

[4] Anthracnose Disease On Monstera Leaves

In the event that you’ve observed a few of tiny yellow, brown or tan spots on the side of the leaves of monstera You’ve got anthracnose. It’s a fungal disease that can affect monstera as well as other plants in the springtime.

This fungus that causes the disease Colletotrichum spp thrives in moist cold and humid conditions. It can also be able to attack monsteras that have been damaged by cold or water.

Common symptoms are:

  • Leaves turn yellow along the edges
  • The edges of the yellow turn to tan, and then dark brown
  • Young leaves will show brown spots, surrounded by yellow shades
  • Cankers or large lesions may be seen on the stems

Treatment

  • The positive side is that anthracnose is not often fatal to monsters. In any event it is important to avoid injuring your monstera. This can increase the number of entry points for the fungus.
  • Dry and hot conditions can reduce the spread. Therefore, it is important to avoid excessively watering, misting or soaking your Swiss Cheese plant.
  • Aeration increases can help. You can isolate your monstera in a room that is airy and has less humidity.
  • Make sure your monstera is healthy to keep it from contracting the pathogen

(Source: University of Connecticut)

[5] Root and Stem Rot

The appearance of yellow spots on the leaves of monstera or general yellowing could be a sign of root or stem decay. The stems that are rotten tend to be brown, swollen, and soft to the touch.

The stem might be able to see some brown necrotic spots. If your monstera is suffering with stem rot it’s likely that it is affected by root rot beneath the line of soil.

It is usually the case in the event that your beasta has been excessively wet, overwatered, or not properly lit during humid conditions for a long duration of time.

The affected roots are typically dark brown or black in color . They have a soft, mushy texture.

A potting mix that is extremely dry can cause damage to the root. In the end, the roots of monstera are more susceptible to fungal diseases like root rot.

Control and Management

  • Do not water, do not wet the leaves and make use of an environment that drains well to control both root and stem rot.
  • A regular routine of irrigation is required. Make sure to water your garden at the time that the top two or three inches of the growing medium is a little dry. Get rid of any water that has accumulated in the dish.
  • Repot your beasta If it is suffering from minor stem rot or root rot. Make sure to trim the affected stems, leaves, and roots. The treatment with a fungicide that is appropriate can prevent recurrence.

[6] Powdery Mildew

Mildew that is powdery on leaves of monstera typically starts with tiny white spots which spread and eventually cover all the plant.

The undersides of monstera leaves a light gray or white powdery dusty appearance.

The leaves that are infested with powdery mildew, however they are not able to process photosynthesizing correctly. In the end, your monstera’s vigor will decrease and will grow slower. The yellow spots on your leaves are among the signs.

The affected leaves will also curl become yellow and then die. In the end, they’ll shed early.

Treatment

  • Prevention is among the most effective ways to prevent mildew that is powdery and can affect your monstera. Find a bright, warm place to your beasta. Be sure that the temperature is over 65 degrees Fahrenheit (18degC) to prevent the growth of powdery mildew.
  • Place the indoor planters at least a feet from each other. Also, trim your monsteras to improve air circulation.
  • Remove any mildewed or swollen leaves at the first sign of sight
  • Mix one part raw or skim milk with nine parts water, then use it to combat powdery mildew. It is also possible to use baking soda or mouthwash, neem oil, and mild fungicides.

[7] Rust

Rust fungi can cause the rusty brown, yellow or orange flecks to appear on the leaves on Monstera plants.

They’re usually located on the undersides of leaves, however they may be found on tops and the stems of leaves.

Pustules or spots that are powdery can appear black or brownish-purplish in certain cases.

Treatment

  • Preventive measures are the most effective way to guard against rust on a monstera
  • A good air circulation system will to dry out and stop the speed of rust. Therefore, trim away rusty leaves. Make sure you have adequate airflow within and around your monstera.
  • Be careful not to overwater, since rust is a major issue in moist conditions.
  • Make your animal happy with Neem oil.

[8] Septoria Leaf Spot

The Septoria monstera first appears as spots of water on the lower surfaces of older leaves.

The center of these tiny spots of water are gray or light tan with darker brown borders. There are also yellow haloes surrounding the spots.

The fungal disease can spread upwards, blemishing the younger upper leaves with yellow-ringed brown spots.

The affected leaves can become stressed and in a position to not be able to photosynthesise which can cause the death of the plant and its fall.

Treatment

  • The first step is to maintain proper gardening hygiene. Cleanse pruning tools, don’t work with wet foliage and clear up any the garden debris, particularly before winter comes around.
  • The treatment for your monstera involves using ziram, copper, and potassium bicarbonate as fungicides. Apply them on a 7-10-day spraying schedule , as required.

[9] Nutrient Deficiency

The leaves of your monstera could be affected by yellow spots due to nutritional deficiencies.

It’s likely to happen when your monstera is deficient in iron, pottasiumor nitrogen, or any combination of the three.

It is usually the case when the medium for growing is depleted of nutrients. It could also be due to inadequate lighting.

Water problems and nutrient deficiencies frequently go hand-in-hand and can exacerbate the issue.

This is because water overflow and underwatering can affect the plant’s ability to absorb minerals from soil.

Solution

  • Repot your monstera afresh. This will ensure that it has the right amount of moisture and nutrients in the medium that is growing.
  • It is recommended to repotte a new monstera plant every year in the early spring until it is fully mature. Be sure to choose one size larger every time you repot. A well-drained, nutritious pot mix is ideal.
  • Include peat moss or compost, and a similar amount of perlite to increase the drainage and fertility.
  • Make sure you feed your beast a balanced liquid fertilizer frequently in the period of growth between May through September.

[10] Bugs on Monstera Causing Yellow Spots

Common monstera bugs create yellow spots on the leaves. This is because the pests eat off specific areas of the leaves.

They also consume sap from your plant, leaving a number of damage spots that appear to be like brown, yellow, or black.

The most frequent bugs you’ll see on monstera are:

  • Mealybugs: These tiny insects appear in white fuzzy or cotton-like clusters on the leaves’ undersides. They’re sap-suckers who excrete honeydew. The yellow spots can be visible under the black sooty mold that forms.
  • The Spider Mites insects are attracted by dry and hot environments. They may appear as colonies of yellow. But, the soft webbing on the stems and leaves gives the impression of a solitary plant.
  • Scale: Soft-scale insects typically infest monstera plants. They appear as tiny raised bumps on stems and foliage. They may vary in color from brown to beige. The symptoms include sooty mold caused by honeydew, yellowing and slow growth.
  • Aphids: Wooly aphids may be the vectors of monstera leaf blight that causes yellow spots on the foliage. The color of the aphids on monstera can range between brown, yellow, black, red, and white.

Control and Management

  • Get rid of most bugs with a powerful blast of water. Some of them will be sprayed with the look of mealybugs by using the alcohol-coated cotton of swabs.
  • Natural predators are available such as lady beetles, parasitic wasps, and the lacewings
  • Every week, applying an insecticidal soap or oil, such as neem, or sprays for insecticides can help eliminate the majority of these

[11] Improper Lighting/Sunburning

Like all plants, your monstera’s chloroplasts aid in the production of chlorophyll that is green-pigmented. This is what allows monstera to enrich the home you live in with lush vegetation.

If it isn’t getting enough sunlight, it doesn’t have enough chlorophyll, and the leaves of your monstera change color, becoming light or pale.

Direct sunlight may also reflect on specific parts of the foliage. This can cause the leaf tissue to lose its elasticity and causes the same issue of yellowing. The leaves that are splashed can exacerbate the issue.

The droplets of water will function like magnifying glasses. They will focus light on areas that are splashed. The result is that your monstera leaves to be strewn by yellow spots.

Solution

  • Keep your monster away from excessive direct light or dark spaces.
  • The location should get plenty of indirect, bright sunlight.

How to Prevent Yellow Spots on Monstera

  • Make sure you have enough airflow by trimming your monstera’s leaves and stems. Place your indoor plants in a space of one foot. Between them.
  • Use good watering techniques – allow 3 inches of potting mix to dry before the next watering. Water splashing, overhead watering, and wetting of leaves are no-no.
  • Maintain a clean and healthy garden Clean up the plant debris, clean the pruning tools, and don’t use on your garden when it’s you are wet.
  • Make sure your pet remains healthy, and is free of diseases and pests straight from the store
  • Make sure you have adequate lighting (bright indirect) as well as temperatures and well-draining growth medium
Stephanie

Stephanie

Went from a bad gardener to a half-decent one over 10+ years. Super happy to share my tips and tricks with you :)