Why Is Your Peace Lily Flower Turning Brown? 12 Important Factors

The Peace lily is a tropical plant that blooms pure-white flowers. Although the flowers naturally turn brown when they reach the end of their life cycle, some factors can cause the plants to turn brown prematurely. So, why is your Peace lily flower turning brown?

Generally, the common causes are overwatering, exposure to sunlight, incorrect temperatures, and low-humidity environments. Other causes are bugs, gray mold, and certain parasites.

In this article, we’ll explore everything you need to know about these possible causes, including their possible solutions. Let’s dive in!

1.   Natural Aging Process

Before you assume the worst, think about the most possible reason why your Peace lilies are turning brown: the natural aging process. Typically, Peace lilies undergo maturity in three to five years.

Their flowers will start green, then turn white. Over time, they will turn green again and fade to a brown color. However, if your Peace lilies are turning brown prematurely, you can rule out their aging process.

2.   Improper Watering

It’s a common mistake for beginner indoor gardeners to underwater and overwater their houseplants. Underwatering will cause the plants to droop because they don’t get enough nutrients from the root system.

Worse, their leaves will turn yellow, and eventually, they’ll become brown.

Although Peace lilies are moist-loving plants, overwatering can do more harm than good. In fact, if you expose them to moist conditions for a long period of time, they can attract bacteria and fungi.

Make sure that the soil is completely soaked through by allowing the water to drain out of the bottom of the pot. You can also check the soil before watering them by inserting one of your fingers into the soil.

If the soil feels damp and sticky, you can skip watering your plants for a day or two. This way, your Peace lilies won’t have too little or too much water. For a more accurate measurement, you can use a soil moisture meter as well.

3.   Too Much Exposure to Sunlight

Peace lily plant set on window sill

Peace lilies are low-light plants. So, exposure to direct sunlight can dry out their flowers and leaves. While they still need dappled light, you need to position them three to five feet back from the windows.

Keep them away from south-facing windows too. That’s because they can expose your plants to sunlight throughout the day and dry them too much. Instead, place them in a north-facing window where they can get just the right amount of sunlight.

4.   Incorrect Temperature

Another possible reason why your Peace lily is turning brown could be the temperature.

Typically, Peace lilies thrive in tropical temperatures ranging between 65℉ to 85℉. Temperatures below 60℉ can damage their leaves, making them turn brown or black.

Moreover, keep them away from air conditioners and heaters. Drafts of cold air and hot air from these devices can also result in brown leaves.

5.   Low Levels of Humidity

In addition to tropical temperatures, Peace lilies need high levels of humidity to thrive. If you keep your Peace lilies in a low-humidity environment, they won’t grow well. The tips of the leaves will wither and turn yellow first. Over time then, the leaves will grow brown and fall off.

Therefore, you should keep the humidity at 50% or higher. To increase or maintain humidity, you can mist your plant. In addition, you can fill a tray with water and pebbles and place the pot on top of the tray.

Better yet, use a humidifier.

6.   Poor Soil Quality

Potting soil and shovels

Your soil mix contributes to the growth of your Peace lilies. Peace lilies prefer a potting mix with excellent drainage. Avoid compact soil as it can cause brown tips and root rots on your Peace lilies.

If you use compact soil, the water won’t reach the roots and will only trickle around the edges of the pot and flow out the drainage.

Another factor that can affect your houseplants is the pot. Avoid using plastic pots because they tend to retain moisture. Instead, opt for clay or terracotta pots as they’re great at absorbing and keeping excess moisture from the soil.

For the nutrient-rich and well-draining potting mix, some of your best options are:

7.   Too Much Fertilizer

Peace lilies don’t require regular fertilizing because they’re not heavy feeders. Generally, you only have to fertilize every six weeks starting in late winter.

Overfeeding makes the flowers and leaves turn brown. You should also avoid strong fertilizers as they can result in root rot.

Avoid fertilizing during winter because Peace lilies usually become dormant. Keep in mind that they only need fertilizer during spring and summer. That’s when they produce new leaves and flowers.

Otherwise, the fertilizer will only lead to salt build-up in the soil. Later on, the salt build-up can cause your Peace lilies to have a higher risk of root rot.

Furthermore, Peace lilies need a well-balanced fertilizer rich in phosphorus, nitrogen, and potassium. Some of the best fertilizers for Peace lilies are:

8.   Repotting During Winter

While repotting is essential for Peace lilies, doing it at the wrong time often results in your plants going brown. Usually, the ideal time to repot your Peace lilies is in spring, when they’re about to grow new leaves.

Avoid shifting your house plants in the winter because they usually go dormant during this time, making it harder to adjust to the new pot. The changes in their growing conditions might even lead to transplant shock.

In addition, leaving your Peace lilies as they are can lead to wilting, browning, and dying. Thus, make sure to repot your plants at the right time.

9.   Chemicals in Water

Giving your Peace lilies tap water that’s high in fluoride and chlorine might result in brown or blackened leaves and flowers. In some countries, tap water can be harsh for Peace lilies. Hence, using distilled water is your best option as it has lesser chemical deposits.

Although watering Peace lilies with tap water is fine in some areas, leaving tap water to sit for too long can accumulate chemicals.

10. Pest Infestation

If your Peace lilies have brown spots, it can be an indication of pest infestation. Examples of pests are aphids and spider mites. These are tiny bugs but they can damage your Peace lilies to a great extent. Its early signs are yellowing and distorted leaves.

Aphids and spider mites attach themselves to the undersides of the leaves and suck the nutrients out of them, hence the brown spots.

To get rid of pests, you can soak a cotton swab with 70% isopropyl alcohol. Use the swab to get the cluster of Aphids or spider mites from the undersides of the leaves.

For larger infestations, you’ll need a strong stream of water to knock them off. Then, spray them with neem oil or insecticidal sprays such as:

11. Fungal Infection

Fungal leaf spot plant disease close up

Fungi spores prefer cool and wet weather in spring. They also dwell in soggy growing mediums. So, if you overwater your Peace lilies and the soil mix doesn’t have adequate drainage, your plants can be susceptible to fungal disease.

Fungal infections, such as Botrytis blight and Cylindrocladium root rot, can cause spotting, wilting, and browning. Some of its early signs are flower buds not blooming and tiny oval-shaped brown spots on the leaves and flower buds.

Root rot, in particular, causes your Peace lilies to lose their leaves. As the name implies, your Peace lilies’ roots get rotten, turning them to a brown or black color. If you examine them by touch, they’ll feel spongy.

You can stop the further spread of fungi by trimming off the affected area. You can use some of the best fungicides in the market like:

12. Bacterial Disease

Like fungi, bacteria thrive in soggy growing mediums. They survive in plant debris and water irrigation and attach themselves to plant foliage by water splashes.

Bacteria are also responsible for your house plants turning brown. Early symptoms are brown and greasy lesions. Then, the browning extends to the leaves and flowers, making them look wilted.

Prune out the infected flower and plant foliage. Bacteria like Xanthomonas easily spread, so make sure that you sanitize your cutting tool before and after using them. You can use bactericides too, such as:

Wrapping Up

So, why is your Peace lily turning brown? If you’ve ruled out the natural aging process of your Peace lily, the possible culprits are improper watering, exposure to too much sunlight, incorrect temperature, and low humidity in the environment.

Reporting, too much fertilizer, and poor quality of potting mix can also lead to browning. Furthermore, look out for pest infestations, fungal diseases, and bacterial infections.

Once you’ve figured out what’s causing the browning of your Peace lily, you can come up with the right solution.

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