Why Are My Lotus Leaves Turning Black? [Causes & What To Do]

Whether you’re growing your first lotus plant or you’re an expert grower, you may notice lotus leaves start to turn black and not know how to solve the issue.

This phenomenon can indicate that your lotus plant is preparing for the dormancy of winter. But, lotus leaves turning black can also be caused by a host of other problems.

You need to be able to determine why your lotus leaves are turning black and how you can address the issue.

Keep reading to find out more!

Table of Contents

Here’s Why Your Lotus Leaves are Turning Black

Several reasons can explain why your lotus leaves are turning black. The most common reasons are:

They have been exposed to water
Insects have found them
They are going through a natural dormant cycle
There are some nutrient deficiency issues
They aren’t absorbing enough sunlight
There are high alkaline levels in the water

Let’s look at a few of these causes of leaf discoloration and see how they can be avoided.

Water Exposure

Lotus plants have developed different biological structures that allow them to live in aquatic environments. There are two types of leaves that Lotus plants have to help them survive.

The first type is called a floating leaf. These leaves float on top of the water and possess properties that help them repel liquids to avoid excessive water damage.

Sometimes, these floating leaves can develop holes due to water droplets amplifying the sunlight on specific areas.

These holes can attract local pests and bacteria that eat and nest in the leaves.

Once bacteria start to take hold on a large scale, they will widen those holes, causing excessive damage to a leaf, and start the rotting process.

You will see this rotting process as the leaves will start to turn brown and eventually black as your lotus leaves begin to die.

The second type of leaf that lotus plants have is called an aerial leaf. Once this leaf matures, it should not come into contact with water.

Aerial leaves are responsible for the sugar production of the lotus plant. If these leaves become submerged in water for too long, they will start to die.

A plant needs oxygen to thrive and perform its processes. When the plant’s production leaves are underwater, they will essentially suffocate from lack of oxygen.

To prevent long-term submersion, you should check on your plants regularly. Certain factors, such as a heavy rainstorm, can lead to leaves becoming accidentally submerged in water.

Read Are Lotus Plants Poisonous to Cats

Insect Infestation

Many different kinds of insects like to attack the leaves of plants because these plants contain vital nutrients.

If your lotus leaves are attacked with enough frequency, your leaves will start to brown. Not long after this, your leaves may turn a black color as they start to die.

Insect attacks typically start at the leaf’s margins and not the leaf’s center, so you should regularly check your plants for signs of infestation.

If you have an excessive problem with insects, you could look into getting a pesticide that can repel these insects and protect your leaves.

Natural Dormancy Cycle

A lotus plant has natural germination and blooming cycle that ranges from late spring and into the summer months, and then the lotus dies during the autumn and winter months.

The process of dying starts with the browning of leaves that turn black as the cycle goes on.

You can speed this process along by cutting off leaves that have completely blackened along the stem, but there is no way to reverse this natural process.

This natural winter dormancy can make it tricky to distinguish between an actual problem with your lotus leaves and a natural process you shouldn’t interfere with.

Read How to Take Care of Lotus Plant at Home

Nutrient Deficiencies

Sometimes lotus plants are not getting the proper nutrients to thrive in their environment.

Nutrient deficiencies can be remedied in several ways. First, you can use a fertilizer that contains extra nutrients for your plant.

If you already use fertilizer, it may be worth switching to a different brand. This will ensure that your plant is receiving a variety of nutrients.

Another way to ensure your plant is kept healthy is to change the soil. Over time the nutrients in the soil can be depleted.

Nitrogen Deficiency

If you start to notice a slight yellowing of leaves, this could be the beginning stages of a nitrogen deficiency.

You will want to address this deficiency before the leaves turn black.

Potassium Deficiency

A potassium deficiency will start as yellowing of leave edges.

This deficiency could also begin as an inability for buds to bloom and turn into pinholes where blackened dead patches of leaves will occur.

Read How To Plant Lotus Bonsai Hydroponic

Phosphorous Deficiency

A phosphorous deficiency will present as older leaves darken into a dark green or purple-green color.

If left untreated, this color will develop along with the plant until the different parts of the plant start to die and then turn black.

High Alkaline Levels

One drawback of using some types of fertilizers is that they will leave behind salt byproducts that can increase the alkaline level of the water around the lotus plant.

Some types of lotus plants have a high alkaline sensitivity which can cause the death of the plant as it gets exposed to the alkaline conditions over time.

High alkaline water has a higher pH which affects the ability of nutrients to be absorbed by the plant.

As the alkaline level increases, your lotus plant will have more difficulty absorbing nutrients. There may come a point where your plant starts to starve, and eventually dies.

You want to mix in fresh water and balance the pH of your plant’s environment to counteract this phenomenon.

Read How to Plant Lotus Bulb in North Florida

Frequently Asked Questions

Before you go, we have compiled a list of answers to commonly asked questions about lotus leaves. These answers might help you if you’re still stumped on what to do if your lotus leaves start turning black.

Why are my lotus leaves rotting?

The most common cause of rotting lotus leaves is when something forces a mature lotus leaf into the water.

Lotus leaves are responsible for producing sugar so that the lotus plant can continue to grow and bloom. If something forces an aerial lotus leaf into the water, it can start to die.

Every plant needs a certain amount of oxygen to breathe. Think of the lotus leaves as the ‘nose’ of the lotus plant; if they are underwater for too long, the whole plant will start to drown.

Lotus leaves can also develop fungal problems when exposed to water because fungus loves to feed on the sugar-rich lotus leaves if it gets a chance.

What fertilizer is best for lotus plants?

Lotus plants thrive with fertilizers high in potassium and lower in nitrogen. Each of these nutrients is important for the growth, flowering, and photosynthesis of lotus plants.

You will want to use an aquatic fertilizer for lotus plants because water is an excellent delivery system for fertilizer nutrients.

Aqua fertilizer comes in the form of small tablets that you can push into the soil of your lotus plant.

Read How To Propagate Lotus Plants?

What kind of soil is best for lotus plants?

Lotus plants don’t thrive in traditional pot soil. The density of traditional pot soil is too low to be helpful in an aquatic environment.

Standard pot soil will float to the top in a lotus plant environment, which is detrimental because lotus plants need soil to anchor themselves to the bottom of their water.

For these reasons, you will want to treat your lotus plants with soils of clay and sand since they are dense enough to sink to the bottom of their aquatic environment.

You will also want soil with low organic material, so they aren’t susceptible to bacterial and fungal infections that can hinder their growth.

Can a lotus plant grow indoors?

A lotus plant can grow indoors, but it’s more challenging to grow an indoor lotus successfully.

Indoor lighting doesn’t contain the right ingredients that lotus plants need to grow. Your lotus plants need harsh and direct sunlight to achieve an effective growing cycle.

Indoor plants can also be susceptible to breezes, fans, and changes in air pressure. These factors can cause your lotus leaves to start to develop dark blemishes or spots.

Read Why my Lotus Seeds are not Germinating?

What do lotus flowers need to grow?

Lotus flowers need various things to thrive, including:

A proper amount of sunlight
Heat
Water
Nutrients

They need 4-6 hours of direct sunlight a day, a shallow pool of water to develop in, and a warm temperature.

If you keep them in a container, they will also need to have a lot of room to grow.

If you start from a seed, you may need to move them to bigger containers as they begin to outgrow the germinating enclosure.

Read Can You Grow Lotus Without Soil?

Final Thoughts

There are many causes for the blemishes in your lotus leaves that can start to turn them black.

Whether you have unknowingly exposed your plants to water droplets, insects, a lack of sunlight, or your plants have a nutrient deficiency; you can remedy each of these problems.

Sometimes, lotus leaves turn black in a natural process related to their life cycle. This cycle signifies their transition into dormancy during the winter period.

Hopefully, now that you’re armed with this knowledge of lotus leaves, you can successfully diagnose any problems and save your lotus plants after noticing black leaves.