Root Rot in Houseplants: Causes and Treatments Guide

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Root Rot in Houseplants

The most damaging and common disease in our houseplants is root rot. An infection can destroy a plant literally from the bottom up. It spreads rapidly, and if not treated, the situation becomes hopeless.

This article will give you an overview of root rot, how it’s caused, how to treat it, even how to prevent it. Prevention is the best policy, but early detection is preferable.

What Is Root Rot?

Plants succumb to root rot when the roots of their roots contract pathogenic organisms that can no longer transport nutrients. Root rot leads to the death of the plants.

Many viruses, bacteria, fungi, and oomycetes can cause root rot. Root rot can quickly spread throughout the whole plant. Common fungi include Fusarium, Pythium, Phytophthora, and Rizoctonia, but they don’t matter as far as basic treatment goes.

Despite being vulnerable in containers, these pathogens don’t just affect houseplants: they cause enormous economic damage to crops worldwide. It’s important to keep your green babies healthy by ensuring their artificial environment does not promote infection.

What Causes Root Rot?

A root-rotting pathogen prefers moist conditions, so soggy conditions usually kick off the infection.


The classic setup for rot is overwatering a plant.

By suffocating the roots and decreasing the soil’s oxygen level, overwatering creates an ideal environment for opportunistic pathogens.

Poorly Draining Soil

In heavy soils, water tends to accumulate, and so the roots stay wet (and dry) to a cement-like hardness. This is why it is specifically recommended to have well-draining soil for most plants.

Inadequate Drainage

Drainage holes are essential for houseplant containers. Putting stones on the bottom does not help: it just preserves a layer of stagnant water below the roots.

Oversized Pots

If you are tempted to give your plants more growing space (and save yourself repotting effort in the future), do not. Excess soil can breed problems, as empty spaces can become waterlogged dead zones.

Non-porous Containers

A big advantage of clay pots is that they are permeable. Water can evaporate from their walls, allowing the soil to breathe, as opposed to nonporous pots like plastic or glazed containers.

Failure To Empty Caches

Houseplants placed in a saucer or cache pot protect underlying surfaces from water drainage, but the soil may become sodden if it remains in contact with runoff.

A good safety practice is to elevate the pot above water level with pebbles. This helps increase humidity in the area, too.

Cool Temperatures

In the controlled temperature of your home, regular watering would not be an issue. However, if the weather cools down, water use as well as evaporation will be higher.

Poor Air Flow

This can also be caused by crowded plants because crowding can also result in poor ventilation and soil that stays wet too long. This issue can also arise due to stagnant air: stagnant air leads to soggy soil.

Planting Too Deep

For some plants, burying the stem invites decay. This does not apply to every species; other plants root along the stem when buried, so you should check the planting specifications before lowering the planting depth.

Watering Out Of Season

In addition to seasonal periods of slower growth or dormancy, many plants require less water during these times, which means that a constant watering schedule can result in accidentally overwatering them.

Symptoms Of Root Rot

Root rot must be detected early to prevent the disease from spreading; unfortunately, the first stages of the disease happen out of sight.

Early Warning Signs Of Root Rot

In general, slow growth or yellowing leaves are early indicators of root problems. You can also check the soil if you see discoloration in the leaves.

The soil remaining moist throughout the day can also indicate a problem below. Curled leaves that seem to recover overnight can also indicate an issue.

Root Rot Red Alert

Swollen stems and brown leaves are classic signs that the disease is in full swing. Since plants rot from the bottom up, the symptoms appear first on the lower stem and leaves. Even though the root system is not yet affected, it will be soon enough.

Symptoms of root rot include limp, yellowing and browning roots. The brown covering of the roots may easily be pulled off to reveal the inner tissue. When the root rot is suspected, gently remove the topsoil for examination.

Another sign of root rot is the odor of decay. It becomes more noticeable as the disease progresses. Once you recognize the odor, you may not need to wait as long to detect the problem. Healthy roots are odorless or have an earthy scent.

The End Game

The disease causes the roots to become mushy, leading to failure of the entire plant. If not treated, the stem may fall off in your hand when you check it.

How To Fix Root Rot

It is best to remove the plant’s pot so that old soil can be removed from its roots. Cut out all diseased roots and leave only healthy roots. Next, repot the plant in a sterile pot and use new, well-draining soil, taking care not to overwater the plant.

It is important to determine the severity and type of treatment based on the condition. Early detection allows for fewer invasive treatments.

Root rot should be treated immediately in all cases. Quick action saves as much of the plant as possible. One day can make a difference.

If you have a compromised plant, you cannot provide nutrients properly until the roots are healthy again. Be sure to keep the plant out of intense light and refrain from fertilizing until the roots are healthy again.

Treating Mild Root Rot

Your plant might seem to be languishing if the soil is wet but there is no definite smell, puffy stems, or any other indication of rot. At that point, you should back off watering and pay close attention to the health of your plant.

It is possible to treat mild infections by simply letting the soil dry out and changing your watering practices. This will prevent repotting, which can delay the plant’s recovery.

To make sure that any pathogens are deprived of excess moisture, remove any mulch or fallen material from your topsoil. Your goal is to allow the natural defenses of your plants to kill them.

You should have good airflow over the pot. If the medium is very wet, remove the roots from the pot and leave the soil in a block on newspaper until it has dried. A fan will speed up the drying process.

Treatment of Severe Root Rot

You need to take desperate steps if the root rot is extensive, but living roots have not yet been destroyed. Repotting your plants will introduce another level of stress, so proceed gently.

Here are the steps:

  • Inspect the roots of the plant after removing it from the pot.
  • Infective soil should be removed from the root ball.
  • Use sterilized shears to cut away brown or mushy roots. (Re-sterilize after use!)
  • Leaves that have wilted or become discolored should be removed.
  • The plant’s roots will perform better if the remaining buds and flowers are removed along with about 50% of the leaves.
  • Pot in fresh, dry, well-draining soil, and start watering again slowly.
  • Resuming a light watering schedule should be done slowly.
  • If rot returns, isolate and monitor the plant. If that does not work, discard it safely.
  • There will be less need for water since there are fewer roots now.

Very Severe Root Rot

Those with the most severe cases will have to throw away their plants. Don’t let them contact your other plants. Sterilize pots and other items that touched them. Dispose of the soil. Short and sad.

How To Prevent Root Rot

Ideally, you should prevent root rot by avoiding mistakes, which means as follows:

Sterilized Well-Draining Soil

Few plants appreciate heavy sludge in their pots. In most cases, heavy soil requires relatively little effort to fix.

Typically, potting medium falls on a continuum between impermeable clay and sand, with most plants preferring a mixture somewhere in the middle. In heavy clay soils, sand, perlite, bark, and other coarse amendments can be added to improve drainage, but vice versa.

If you are working with sandy soil or clay soil, organic amendments like worm compost can help it drain better and offer natural fertility as well.

Correct Watering

Water your houseplants a little at a time. Succulents need less water than tropical plants, and even water-hungry potted plants do not like being constantly wet.

If the pot becomes saturated with water, let it drain thoroughly. Let the soil dry between waterings. Dry out the soil during winter or dormancy.

Proper Potting

A plant’s root system determines its container size. Some plants such as tubers and epiphytes have confined roots, but others have roots that extend deep.

A garden bed that has no roots can develop dead zones where root rot may take hold. One size doesn’t fit all, so make sure the soil is aerated and able to take up water.

Additionally, clay pots have the benefit of allowing moisture to evaporate through the sides and allowing the soil to breathe.

Give Them Room

It is essential that your plants are not stagnant (or contaminated by each other) so make sure there is sufficient airflow around them.

Plant Choice

Also, the kind of plants you choose makes a difference. Some plants are prone to root rot.

A cactus’s roots naturally require less water than those of other plants, which make them susceptible to disease and root rot. Epiphytes, too, have weak roots designed primarily for anchoring rather than taking up water and nutrients, so they can also develop root rot.

You could choose to stick to moisture-loving plants if you are not in complete control of your watering can. Peace Lilies are hard to overwater, and many ferns prefer constantly moist conditions. However, even these plants will not appreciate soggy soil.


In order to combat root rot, the most crucial tool to use is constant observation. Even experts admit a major reason for failure has been inattention.

Develop the habit of watching your plants and reacting as needed. Check for abnormalities in their growth or color. Monitor the rate at which the topsoil dries out. Be aware of the timing of watering. Watch for signs of dormancy.

If you pay attention to your plants, you can usually avoid the pain, the guilt, and the smelly mess of root rot. Plants do not talk, but they do communicate. Become a green thumb by learning their language.

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