Brown Leaves in King Anthurium (7 Reasons)

King anthurium, also known as Anthurium veitchii, has foliage that can grow up to 2 meters long! Now the term “king” makes more sense, right? With that huge leaf size, it is just right to do all you can to prevent browning!

Generally, the development of brown leaves in king anthurium is caused by sunburn, low humidity, water-clogged soil, bacterial blight, lack of sanitation, insects, and excessive fertilization. However, each of these can be prevented through various strategies including the use of humidifiers and placement of the plant in a shady area.

What are the more appropriate ways to control different factors that cause leaf browning? Answers will be revealed as you read on!

1. Sunburn

Intense sunlight can cause leaf sunburn in Anthurium veitchii and lead to browning. King anthurium plants with smaller leaves (1-2 ft) are best placed in a west-facing window when grown indoors. But bigger king anthuriums (>3 ft) can be grown in a shady outdoor location.

King anthurium is native to the rainforests of South America having both arid and humid weather. With this environmental origin, the surrounding temperature for king anthurium must be balanced for optimal growth. Thus, they thrive under bright, but indirect light.

Indoor King Anthuriums

If you are growing king anthurium indoors, you can use a west-facing window to take advantage of the bright afternoon sun.

Here’s also a gentle reminder to not place your king anthuriums near a south-facing (light is too intense) or a north-facing (light is too weak) window.

Outdoor King Anthuriums

On the other hand, if you are growing mature king anthuriums outdoors, look for a place where there is enough shade. This can be under a tree or inside a greenhouse.

A unique characteristic of king anthurium is it can attach itself to surfaces and crawl like a vine. It can spread towards tree trunks or even dominate poles. So if you do not want its leaves to start browning, make sure that wherever you place king anthuriums, there is shade.

2. Low Relative Humidity

Leaf browning occurs when the relative humidity for king anthurium is lower than 60%. With this condition, the leaves of Anthurium veitchii are denied water access—leading to their dehydration, and eventual browning. Pebbles can maintain high humidity for outdoor king anthuriums, while humidifiers are best used indoors.

Did you know that houseplants like anthurium can absorb moisture from the air? This is the reason why humidity plays a huge role in maintaining these plant types.

Aside from water from the soil, king anthurium plants can also make use of moisture from the air to continue biological processes such as photosynthesis.

Fun Fact: Compared to other anthurium species, king anthuriums require higher humidity of more than 60%. So you have to be really mindful about keeping the space you’re keeping your Anthurium veitchii humid enough.

Indoor King Anthuriums

When growing king anthurium indoors, using a humidifier filled with distilled water will increase humidity if the air in the room is too dry.

Remember to only use distilled water—not tap, soft, or hard water. Why? Because these water types are potential sources of minerals and salts that can damage the leaves of your king anthurium plants.

   Head to our article explaining the different water types to know more about this.  

This essential oil diffuser on Amazon is best for indoor gardens.

This humidifier might be the best choice if you are growing relatively larger king anthurium plants.

Outdoor King Anthuriums

Since king anthurium leaves can grow up to 6 ft, mature plants cannot be maintained indoors. With an outdoor set-up, it is difficult to control humidity and obviously, you cannot use a humidifier—plus, it is not practical!

Luckily, we can use the power of pebbles!

When growing outdoors, you can use pebble trays. The surprising thing is you can actually create one yourself! You just need to get a flat tray and simply put pebbles in it. After this, just add water to the pebble tray and place your potted plant on top of the tray.

Maybe you are wondering, how is this effective?

With this setup, the water slowly evaporates—elevating the humidity around the plant— because some of its molecules are attached to the surface of the pebbles. You can do the same for king anthuriums that climb on trees. You can just put pebbles below the tree and wet the pebbles every day to increase relative humidity.

Caution: Do not mist water directly onto king anthurium leaves using garden sprays (indoors) or hoses (outdoors). This is not recommended since the big water droplets they release can be breeding grounds for bacteria and fungi in the leaves.

3. Water-Clogged Soil

Overwatering king anthuriums is another cause of leaf browning. A water-clogged soil results in oxygen scarcity for the roots which then leads to its rotting. As a result, plant vigor decreases followed by drying and browning. With this, a watering schedule of 2-3 times a week is the best formula.

Remember this: Harmful microorganisms, like bacteria and fungi, develop and thrive in wet environments.

Root rot has been a major outcome of overwatering. The sad truth about doing this is it will gradually weaken the immune system of your king anthuriums and will lead to plant death.

How to Spot if You are Overwatering Your King Anthurium?

When the top portion of your soil is wet at all times, it is time to shake things up! Consider lessening your watering schedule to only 2-3 times a week during summer and as often as every 10-14 days during winter.

4. Bacterial Blight

Bacterial blight is another possible reason for Anthurium veitchii leaf browning. Microorganisms can enter the plant through leaf damage such as wounds and insect cuts. To prevent bacterial transfer, sanitizing garden tools with ethyl alcohol is advised.

For bacterial blight, it starts with yellowing that eventually dominates the leaf until it becomes brown.

To avoid the development of bacterial blight in king anthurium, keep the following in mind:

1. Do not overwater
2. Maintain a 70-80% relative humidity
3. make sure that air circulates well
4. Avoid getting the leaves wet

5. Lack of Sanitation

Inadvertently spreading plant diseases is due to the non-sanitation of garden tools such as scissors and shovels. As such, it is important to regularly sanitize and disinfect all the tools and equipment one uses to tend to their garden.

Let me ask you, what is the first thing that comes to your mind when you see brown leaves dominating your garden? If you are someone like me, perhaps you are yelling: “I want to get rid of that! Let me cut that leaf!”

I hate to break this to you, but those very scissors can be carriers of bacteria and fungi. So, my advice is to disinfect them before and after using them to cut the brown leaves!

A wide range of disinfectants can be used for this. You may opt to use food-grade hydrogen peroxide, diluted bleach, or even 70% ethyl alcohol!

   Know the difference between disinfectants in our article on hydrogen peroxide vs bleach.  

How to Sterilize Gardening Tools : Smart Gardening

Sanitation is not only about garden tools. It also involves overall garden sanitation—meaning letting go of plants that can potentially spread disease.

So what’s the wisest thing to do when the majority of your king anthurium leaves are already affected by bacterial blight or wilt? Discard the whole plant!

Common Gardening Mistake: Do not use an infected plant as a material for your compost.

This is because the causal bacteria is still present in the plant debris and may spread in your compost. The bacterial transfer is a huge possibility that can infest the plants you will be growing with the compost.

6. Problematic Insects

Insects like spider mites and mealybugs infest Anthurium veitchii when they destroy the leaf surface and drink the plant juices. After sucking the juices, these insects excrete honeydew that attracts other pests. Thus, it is also a key to wipe this fluid in the leaves using a clean cloth. Insecticidal soap can also be used for pest control.

The first thing to do is to assess your indoor garden for insect pests.

Below are some of the signs of pest infestation in king anthuriums:

1. Silver streaks
2. White webbing
3. Black droppings

If you observe these signs on the surface of king anthurium leaves, you may opt to spray them with insecticidal soap once a week. This product is available on Amazon and the one below is much-recommended.

No products found.

Another helpful product you can use as an option is neem oil. This amazing product I have been using ever since is available on Amazon.

No products found.

You can also remove the insects by hand together with their excreted honeydew fluids using a clean cloth or cotton ball dipped in 70% ethyl alcohol.

7. Excessive Fertilization

Do not fertilize king anthuriums excessively because this will lead to mineral and salt buildup and eventual browning. The recommended fertilizer ratio for king anthurium is 9-6-0 of N-P-K. This must be applied every 6-8 weeks from March to September.

But be very cautious in using synthetic fertilizers. When there is an oversupply of fertilizer in the soil, all the extra salts and minerals can block the pathways of water toward the plant’s roots. Without enough water supply, king anthurium leaves are dried up and further turn brown.

To avoid this situation, you can switch to using organic compost. By doing this, you are reducing the chances of salt and mineral build-up from synthetic nutrients since compost is made of materials that can decompose.

   Explore more about fertilizer types in our article on organic vs inorganic fertilizer. 

FAQs

Should I cut brown King Anthurium leaves and up to where?

Yes, it is advised to get rid of infected King Anthurium leaves. Cut it up to the base to allow the plant to spend its energy on new leaf growth and development. This way also allocates ample space for the new foliage to grow.

What to do when my Anthurium leaves are wilting?

Bacterial wilt is one of the most damaging plant pathogens for Anthurium. The disease starts with the yellowing of leaves that ultimately turn brown. As a remedy, you can use fungicides with phosphoric acid. If the wilting dominates the whole plant, discard your Anthurium.

How do I know if my anthurium is dying?

When your anthurium plant already has a majority of wilting and brown leaves, chances are it has come to its end. But, if it only has brown spots or leaf edges, you can still save it by cutting the leaf up to its base and/or repotting it.

Summary of Brown King Anthurium Leaves

King anthurium leaves turn brown due to intense sunlight, moisture deprivation, water-clogged soil, bacterial blight, lack of sanitation, problematic insects, and excessive application of fertilizers.

Generally, water deprivation is the starting point of brown anthurium leaves. Thus, it is important to provide water resources in the form of humidity or in the soil. Having excess fertilizer in the soil hinders water from being absorbed by the roots. Pests and diseases also cause physical damages that make king anthurium leaves brown.

To prevent browning, locate anthurium plants in shaded places. Growing with pebbles and humidifiers is a strategic way to increase the relative humidity up to more than the ideal 60%. Watering only every 2-3 days is the optimum watering schedule. Lastly, sanitizing garden tools and the leaves can also hinder browning.

Sources

• “Anthuriums” by Institute of Food and Agricultural Sciences in University of Florida
• “Anthurium Diseases: Identification and Control in Commercial Greenhouse Operations” by Norman, D.J. and Ali, G.S. in University of Florida
• “Cultural Guidelines for Commercial Production of Interiorscape Anthurium” by Chen, J., et al. in University of Florida Institute of Food and Agricultural Sciences.
• “Overwatering” by Missouri Botanical Garden