Peace Lily Leaves Turning Black – Causes & What to Do

Have you noticed that your Peace Lily leaves are starting to turn black? It’s a scary sight, but don’t worry it doesn’t mean your plant is dying.

Usually, Peace Lily leaves turn black due to fungus infections and pest infestations. There are other causes of black leaves, such as improper watering, overfertilization, and improper soil. However, the best way to save your peace lily plant is to identify the problem early on.

Continue reading this article to find out what causes black leaves on Peace Lilies. Additionally, I will discuss how to resolve these issues and prevent them from occurring again.

Why peace lily leaves turn black

Why peace lily leaves turn black

1. Plant Age

The peace lily will grow new foliage by shedding the old one. This is a natural process where your plant will become black from the tips. Once peace lily leaves turn black they will shed and new leaves will grow to replace them.

What to do:

  • As it is a natural process, there is nothing to worry about. However, you can prune the black leaves at the base of the plant. 
  • Make sure to use sterilized scissors. Additionally, do not prune new leaves.

2. Improper watering

This means both underwatering and overwatering. In the rainforest, rain showers are common. Therefore, peace lilies don’t tolerate underwatering. It is very likely that the Peace lily will shrivel and die if not watered.

Underwatered peace lilies cannot transport water to other parts of the plant because the roots are too dry. Moreover, it affects the transport of micronutrients needed by plants for proper growth. Because of this lack of water and micronutrients, the peace lily appears shrunken.

Alternatively, overwatering can cause even greater damage. Watering peace lily with too much water will make the soil soggy. As a result, the root environment becomes anoxic (contains no oxygen), suffocating the roots.

What to do:

  • A consistent watering schedule is essential for peace lilies. 
  • Do not let the soil dry out or create a stinky swamp in your planting pot. 
  • Make sure the soil is moist, but not soggy.
  • Cut off decayed leaves using sterilized scissors. In this way, nutrient transfer to unproductive leaves will be prevented.
  • Ensure drainage holes are functional to prevent waterlogging. Also, don’t let your peace lily sit in water for too long.
  • A soil mix’s drainage capacity is also important. 

3. Water quality

Impurities such as fluoride, chloride, and bicarbonate are usually present in household water.

It is unlikely that your Peace lily will thrive in a water of such quality. As a result of those compounds, soils can become salinized or even acidified.

As the salt in the soil builds up, the plant won’t receive the water efficiently. Water is blocked from roots and plants by soil salts.

Additionally, a lack of nutrients such as potassium, magnesium, and phosphorus causes the plant’s leaf color to change. Leaf color changes to yellow, brown, and purple with black spots.

What to do:

  • Using tap water will cause dark stains on your peace lily’s leaves very quickly. However, it is possible to reduce fluoride and chloride concentrations in tap water by filtering. Also, you can use distilled water.
  • In the absence of a filter,  let the water sit for 24 hours before using it. As chlorine evaporates, the water will be less harmful.
  • Your plants will thrive if you collect rainwater. For future use on your plants, you may save water in a large container.

4. Fungal Disease

Anthracnose, black spot, and sooty mold are just a few of the fungal diseases that can affect peace lilies. Let us understand each one in detail.

Anthracnose 

  • Dark brown or black spots appear on the leaves due to anthracnose, resulting in leaf drop.
  • As the fungus grows in cool, damp environments, it’s crucial to water your plant only when it’s dry and to keep the leaves dry as well.

Black Spot

  • In black spot fungal disease, black spots appear on leaves, resulting in leaf drop.
  • Similar to Anthracnose, black spot grows in cold environments. Hence, only water your plant when the soil is dry.

Sooty Mold

  • On Peace Lilies, sooty mold grows as a black fungus. It’s not harmful to the plant, but it looks bad.

What to do:

Follow these steps whenever your peace lily shows signs of fungal infection.

  • Keep the plant away from other plants. It will prevent the spread of the fungus.
  • If the leaves are damaged, you can also remove them and dispose of them.
  • Before and after use, sterilize your pruning tools to avoid the spread of disease.
  • Fungicides can be used to treat the plant, but follow the directions on the label carefully.

5. Bacterial Disease

In bacterial diseases, peace lilies are susceptible to:

Bacterial Leaf Spot

Small, dark spots appear on the leaves when bacterial leaf spot develops, and eventually, the leaves drop.

Bacterial Blight

Symptoms of bacterial blight include small, dark spots on the leaves surrounded by yellow halos.

What to do:

  • Dispose of any leaves that are affected.
  • Prior to and after using pruning tools, ensure that they are sterilized.
  • Additionally, you can use a bacterial fungicide to treat the plant, but pay attention to the label instructions.

6. Root rot

In Peace Lilies, root rot can be a serious problem. Fungi such as Pythium and Phytophthora cause it.

Rot occurs when these fungi attack the roots of the plant. If root rot is left untreated, the plant will eventually die.

Hence, only water your plant when the soil is dry since root rot is often caused by overwatering.

What to do:

  • The first step is to remove the plant from the pot and examine the roots.
  • It is likely that the roots have rotted if they are black or mushy.
  • In this situation, it is best to remove the rotted roots from the plant and replant it in fresh soil.
  • To prevent the spread of disease, sterilize your pruning tools before and after use.

7. Overfertilization

In order to grow well, peace lilies don’t require much fertilizer. Also, plants can get sick from too much fertilizer.

Too much fertilizer or too frequent fertilization can burn the roots of Peace Lilies. In these situations, the leaves of a Peace Lily can turn brown, black, or yellow.

What to do:

  • It is best to stop fertilizing your Peace Lily for a while if you suspect that it has been fertilized too much.
  • If there is excess fertilizer in the soil, you can rinse it with water to remove it.
  • In spring and summer, when your Peace Lily is actively growing, use a half-strength fertilizer.

8. Temperature stress

Tropical rainforests are peace lily natural habitat, so they like warm, humid conditions. Although they can handle some temperature fluctuations, extreme cold or heat can damage them.

It is possible for the leaves of the plant to turn black in extreme temperatures. If the leaves appear wilted or dried out, the leaves have turned black from temperature stress.

It is common for the leaves tips to become black and brown if they are exposed to too low temperatures. In excessively hot temperatures, the leaves turn black and dry.

What to do:

  • The best thing you can do if your Peace Lily appears to be suffering from temperature stress is to move it to a place where the temperature is more consistent.
  • Bring inside the plant if it is outdoors. Additionally, whenever you keep plants indoors, put them where they won’t get direct sunlight or near heat sources.

9. Cold injury

Peace lily resides in the tropics with temperatures above 25ºC (77ºF).

In too low a temperature, peace lily would not survive. Hence, a cold room is not a good place for this plant.

Additionally, a chilling temperature causes root function to deteriorate, and leaves don’t evaporate well.

Hence, due to impaired metabolism, leaves start to wilt. As soon as the plant thaws, you see black spots on the leaves.

What to do:

  • Place the Peace lily in a room that is warmer. 
  • If you see decayed leaves, don’t trim them off right away. This will prevent further injury to the plant by insulating it. However, in case of bacterial or fungal infections, you must remove the leaves.
  • In spring, prune off the injured leaves to form a callus at the injury point to prevent cold injury in winter.
  • It is recommended to keep a peace lily in a room that doesn’t drop below 15ºC (59ºF).

10. Humidity

A peace lily prefers humid places and can’t tolerate dry air for long periods of time.

In rooms with air conditioning, heat generators, and ovens, your Peace lily is likely to have blackened leaves.

As a result of dry air, transpiration rates increase. This results in the plant losing more water than it receives.

Eventually, the entire plant becomes dehydrated and shriveled. If there is any flower, it will also dry out and turn black or brown.

What to do:

  • You can increase the humidity of the room by grouping peace lilies with other tropical plants. Together, they create a special microclimate with a higher humidity percentage.
  • Mist around the Peace lily to create a moisture fog. Early in the morning is a good time to do this.
  • When it comes to increasing humidity at home, humidifiers do help. You can place one near your peace lily. It is certain that the plant will flourish with the additional moisture.

11. Low light

As the peace lily prefers shade, keep it out of direct sunlight. However, low light levels may result in pale leaves.

It’s essential to expose peace lily to enough sunlight to build up sugar, which will provide energy.

What to do:

  • The peace lily prefers indirect sunlight. So, on the east side of the room, place it in a bright room with large windows.
  • Additionally, you can increase the light level with LED bulbs because they don’t generate heat.

12. Too much sun

It’s not a good idea to grow peace lilies in direct sunlight since they prefer shady conditions. In indirect sunlight, they thrive, but in direct sunlight, their leaves can be damaged, especially when exposed for long periods.

Overexposure to direct sunlight can cause the leaves to burn and turn black. The leaves will also look brown if they have been sunburned.

What to do:

  • To reduce the amount of sunlight your Peace Lily receives, move it to a shadier location.
  • A north- or east-facing window will give it bright indirect light without direct light.
  • To filter the sunlight, you can also cover the plant with a sheer curtain or blind. Additionally, it is not possible to recover sunburned leaves, so they must be cut off.

Also Check: How to Fix a Peace Lily with Brown Leaf Tips

13. Pests

There are a variety of pests that attack peace lilies, including aphids, mealybugs, spider mites, and thrips.

It’s common for black leaves to be caused by sap-sucking pests such as aphids, mealybugs, and spider mites. As a result, the leaves of Peace Lilies can curl, yellow, or wilt.

A thrip is a tiny winged insect that feeds on the cells of plants. These insects can turn Peace Lily leaves yellow, black, brown, or black. It can also make the leaves distorted or white.

What to do:

  • Isolate your Peace Lily if you suspect it has a pest infestation. Pests cannot spread this way.
  • With rubbing alcohol and a cotton swab, you can remove the pests.
  • Neem oil and insecticidal soap can also help. Also, it’s a good option if you don’t want to use chemicals.

14. Physical Damage

The fragility of Peace Lilies makes them vulnerable to damage from physical trauma.

If something hits the plant or if it’s dropped, the plant can suffer damage. In this case, blackening will occur to the leaves because the damaged tissue will die.

What to do:

  • The first thing you need to do is examine the plant carefully.
  • On the leaves, look for any signs of bruising or injury.
  • In the event that you find any damaged leaves, please remove these carefully and dispose of them.
  • After you have completed the above steps, water the plant as usual, and it should eventually recover.

How to prevent black leaves on peace lily plant

How to prevent black leaves on peace lily plant

Giving Peace Lily leaves the necessary care will prevent black spots from appearing. If you want to keep your Peace Lily healthy and black spot-free, here are a few tips:

  • Indirect sunlight is best for peace lilies. A leaf that receives too much sunlight will turn yellow, then brown or black.
  • Make sure the soil above the top inch of your Peace Lily is dry before watering it. Leaf spots can occur when leaves are overwatered.
  • Choose a well-draining potting mix. As in wet soil, Peace Lilies do not thrive.
  • During the growing season, fertilize your Peace Lily every two weeks. If you are using a balanced fertilizer, dilute it with half strength.
  • If you see any yellow or brown leaves, remove them as soon as possible. These leaves are incapable of photosynthesizing and are draining the plant’s energy.
  • Make sure your Peace Lily leaves do not get wet. There can be fungal growth on leaves and leaf spots if there is water on them.
  • Don’t ignore pests. It is possible for aphids, mealybugs, and spider mites to cause leaf spots. Be sure to treat any infestations as soon as possible.
  • Lastly, dust or brush the leaves of your Peace Lily regularly to keep them clean.

Few questions on peace lily leaves turning black

Q1. Should I cut off damaged peace lily leaves?

Ans. Yes. By pruning out the damaged leaves, the plant can devote all its energy to producing new foliage. Cut the leaf stem at its base to remove the leaves.

Q2. How to prevent the blackening of Peace Lily Leaves?

Ans. Make sure Peace Lily is properly cared for. For Peace Lily to thrive, it must be exposed to indirect sunlight, maintain a temperature of 68 degrees Fahrenheit (20 degrees Celsius), and have a well-drained pot. Moreover, it is ideal to use a potting mixture that has perlite and holds water to keep the soil moist.

Q3. What to do when peace lily plant leaves turn black?

Ans. Black leaves can occur when plants are overwatered. It is often too late to save the plant by this stage, as the rot is irreversible. In order to prevent this, don’t let your plants sit in too much water, and be sure that the pot they are in has a drainage hole at the bottom.

Conclusion

Black leaves on peace lilies can be caused by several factors. Some of the most common causes are fungal disease, lack of humidity, improper watering, and lighting problems. However, you won’t be able to get black leaves on peace lilies if you take good care of them.

Maintain a regular watering schedule for your peace lily and provide it with indirect sunlight. You will not have to worry about your plants‘ leaves being scorched by indirect sunlight. For peace lily, maintain a temperature of 25°C.

However, pests or fungi, or bacteria can sometimes attack your plant. When that happens, you can use fungicide or repot the plant.

The most important thing is to identify the problem and take action accordingly in order to keep your Peace Lily happy and healthy.

So, what questions do you have? Feel free to ask in the comment section. Share this article with your friends and family.

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Author

  • Vinni Balyan

    11 years ago when we left NY and started living in the suburbs, I developed the passion for gardening. I'm a mom of two, and a big time gardener here helping you pick you right battle in gardening. 🙂 Stay tuned.

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