Solving Root Rot: What Causes Root Rot, How To Get Rid of and Treat Plants

Root rot is the bane of many indoor plants. And, if you are a houseplant fan, you may have heard of or encountered root rot.⁶

Thankfully, it’s pretty easy to detect if you’re wondering, what are the signs that your plant has a root infection? And as long as you don’t let the signs and symptoms may sneak up on you, it can be treated.

However, the key to preventing root rot is ensuring that the plant’s watering needs are met.

Because it’s better to catch a fungal infection in its infancy before it’s too late, providing adequate drainage is crucial.

This guide explains all you need to know about how to prevent root rot, what causes it, and how to treat your indoor plants if you suspect a root rot infection.

What Causes Root Rot?

Before you know what causes root rot, you must understand what exactly is root rot. This is a fairly common houseplant disease that results from fungal or bacterial infection.

The habitat of these bacteria and fungi is wet soil and as they grow, they make plant roots suffocate.¹ Sometimes, Root rot is caused by exposing roots to overly moist conditions for long periods.

(Image: Cloud11¹²)

Roots can be considered the engine of the plant. They are responsible for keeping all parts of the plant running and providing nutrients to all the foliage that is above the surface.

As such, when roots die, then the rest of the plant will follow.

Root rot is caused by:

#1 Overwatering

This is by far the most common cause of root rot especially in house plants.⁷ These plants have different characteristics and therefore different water needs.

For example, the ten types of Bonsai Trees have different needs. If the plant is watered too heavily or too frequently, the soil gets oversaturated and becomes a breeding ground for bacteria and fungi.

If you want to know whether you are overwatering your plants, here are a few telltale signs:

• Soil is always wet: If the soil is wet to touch every time, then this is a sign that you are overwatering.
  If you haven’t watered recently, you can check on this issue by feeling the soil an inch beneath the surface. If the soil is still moist from the last time you watered it, then it’s oversaturated with water.
  The best solution for this issue is to get planters with drainage holes that do not allow moisture to pool in the soil.
• Leaves are yellowing: Leaves can yellow when they have too much water or don’t have enough water.
• Having squishy and soft stems: If the stems get soft and squishy, this indicates that the plant is absorbing too much moisture and has started to puff up and lose its firmness.
• Having brown edges or spots on leaves: When the leaves have too much water it saturates their cells leading them to burst foaming brown spots.
  However, similar to the yellowing of leaves, this can also be a sign of under-watering. The rule of thumb is if the browning is on the edges of the leaves then it indicates under-watering but if the browning is in splotches in the middle of the leaves then it indicates overwatering.
• Attracting pests from the soil: Most pests such as gnats love to dump soil. If you notice pests hovering around your plants, then it’s time to scope things out.

You should gently shake the plant out of the container and examine the root system. If there is an overwatering issue, the roots will darken and feel mushy when touched.

Additionally, the plant may give off a funky sour smell due to the bacteria (that love water) forming around the root.

#2 Poor Drainage

Poor drainage from materials used to plant and the pot itself can lead to soil saturation.

If you want to invest in a house plant, make sure that the pot comes with a drainage hole otherwise water will not be able to escape causing excess moisture in the soil.²

One simple solution is to add pebbles and rocks to the bottom of the closed pot to increase aeration but experts recommend getting pots that have drainage holes.

#3 Under-Watering

In some situations, if your plant is receiving less water than needed, it may lead to Root rot. When the soil dries up, roots begin to shrivel and shrink.

Under-watering also leads to a wide range of other problems.

In a case where you’ve forgotten to water the plant in a while and then flood it with moisture, the now-fragile root system can get shocked leading to a myriad of issues such as Root rot.

What Does Root Rot Look Like?

You are obviously wondering; what does root rot look like? It’s fairly easy to identify. The roots are either black or dark brown.

However, the main indicator of potential Root rot is black and yellow leaves. The discolored leaves might also seem shriveled and dry despite watering the plant regularly.

(Image: Hanna Friberg¹³)

Second, if small fungus gnats settle around the plant, this can be an indicator of Root rot. The soil is too moist and has become a breeding ground for fungi and bacteria.

The last clue is the smell of the soil. What does root rot smell like? Root rot brings out a rotting sour, eggy odor.

Succulent Root Rot

Succulents are not usually prone to insect or pest infestation. However, overwatering may result in rotten stems and roots.

If you are learning how to care for succulents and you notice that the plant has stopped growing and is showing signs of succulent root rot, the first step is to remove the succulents from the pot. If the roots are dark brown or black, then they are infected.

Root rot in succulents should be treated immediately or the plants will die. Additionally, the rot will spread to the stem and leaves making them become paler and yellow.

The leaves of your succulent will become mushy over time and the lower leaves will become pale. However, you should note that yellowing leaves in succulents may not be necessarily a sign of root rot.

It could also indicate a nutrient deficiency.

Hydroponic Root Rot

Root rot does not affect house plants only, sometimes it may spread to plants on the farm such as hydroponics. What causes hydroponic root rot?

This type of root rot is caused by a fungus called Phytophthora which is a water-born organism whose main habitat is damp,⁸ oxygen-poor environments.

The fungus populates the roots blocking them from absorbing water and nutrients and killing the plants gradually.³

The most challenging part of root rots in hydroponics is that the fungus rarely stays isolated on a singular plant. Rather, it tends to spread throughout the farm or greenhouse, and spores are easily carried away by the nutrient solution.

This means that most of the plants in the area will suffer damage unless proper action is taken.

If you want to detect root rot in hydroponics, the fast step is to remove the plant and examine the roots. If they have a creamy white color, then they are healthy.

(Image: 41330¹⁴)

If they are dark brown or black, then they may have Root rot. However, the nutrient-rich solution can also stain the plants.

One other sign to look out for is that infected roots tend to feel slimy. Additionally, Root rot often produces an earthy smell which is not usually there in hydroponic farming.

Signs of Root Rot: Symptoms

Signs of root rot include:

• Plants randomly dying
• Stunted growth
• Wilting plants
• Slight deficiencies
• Chlorosis
• Burning
• Spotting of leaves
• Curling of leaves
• General plant stress

Root rot symptoms mirror pest infestation symptoms making them very difficult to detect or diagnose. However, the symptoms are much easier to sport above ground they include:

• Quick and gradual decline with no notable reason
• Poor or stunted growth
• Pale, small leaves
• Browned, yellow or wilted leaves
• Branch dieback
• Canopy thinning
• Cankers and sunken dead areas on the inner bark

Root Rot Treatment: How To Get Rid of Root Rot

Root rot is treatable if caught early. However, if left untreated for too long, it could kill your plant.

Additionally, it’s difficult to cure Root rot that is already established.

In this case, the best solution is to get rid of the dying rotten parts and hope for the best. Once you’ve taken care of the dying parts, consider replacing the old soil with fresh soil.

Ways to treat root rot include:⁹

Trimming Off the Affected Roots and Leaves

If the Root rot spreads through most of the plant and is affecting the foliage and roots, then it’s too late to save it. You can only save a plant if there are healthy roots left.

This rehabilitation can occur by taking the following steps:

1. Removing the plants from the soil and inspecting their roots: When you notice signs and symptoms of root rot above ground, the fast step is to remove the houseplant from the pot. Then, break as much soil away from the roots as you can. Do this process gently to avoid damaging the root further. The next step is to identify the part of the roots and leaves that are rotting. As mentioned previously rotting roots will appear dark brown or black. They will also be squishy or stringy. Healthy roots have a green or white appearance and are very firm
2. Cut away the rotting parts of the plant: Use a pair of pruning shears that are sharp and clean to gently cut away the rotting parts. You have to get rid of all the affected leaves and roots. Be careful not to damage the healthy parts as they are required for plant rehabilitation.
3. Put the plant in a pot with fresh soil: Once you have gotten rid of the rotting parts, put the plant in a pot with new fresh soil. It’s very important to not use old soil because it’s full of root-destroying bacteria and fungi. This time choose a container that has holes for drainage and make sure you use the appropriate soil mix for your plant.

Using the ‘Drying Technique’

The first step is to allow the Succulents or house plants to dry out. This potential cure is beneficial for plants that have been overwatered however, the technique does not yield positive results every time.

(Image: Gary Barnes¹⁵)

Additionally, it’s effective only when the rot is contained in the roots and has not spread to the stem. The technique also works if the leaves of the plant have not turned yellow.

All you have to do is take the plant out of the pot and let it dry for a few days. It’s very difficult to predict whether the plant has been cured so you should repot the plant after a couple of days.

If you check again and find that the roots are not fixed completely then consider leaving your plant out of the pot for a couple of days. Be sure to use fresh soil when potting the plants.

Dust in Some Sulfur

Root rot in Succulents can be treated by powdering some sulfur on the roots. The chemical is mostly used to acidify soil and you can powder some on the roots before repotting the plant.

The sulfur will protect the roots of the succulent from bacteria and fungi.

It’s important to note that since sulfur kills microbes, it may also damage the beneficial ones. However, it can kill the fungi and bacteria responsible for Root rot.

Experts do not recommend using sulfur for rotten roots that result from overwatering.¹⁰ If you want to try out this method, make sure that the roots are dry before dusting with sulfur.

Beheading the Plant

This should be used as a last resort. In a case where the rot has spread to the whole plant which includes the leaves, stems and roots, then beheading the Succulent could save it.

Beheading is similar to propagation which can save a part of the plant. Beheading should be used only in the most critical conditions.

Even so, you must know that Succulents with rotten steps have little to no chance of survival. You could propagate with healthy cuttings as a last resort to save the drought-tolerant plant.

(Image: Teona Swift¹⁶)

For this process, you will need to cut the stem two inches above the rotten part and plant it in soil. Water it for a few days and it’s possible that the cuttings will transform back to a healthy succulent.

Solving Root Rot: How To Prevent Root Rot

The best way to solve Root rot is prevention. Here are some preventive measures for Root rot.

#1 Avoid Overwatering

The best way to prevent Root rot is to avoid overwatering. You can do so in the following steps:

• Knowing the watering needs of your plant: You need to be familiar with the specific water and care needs of your plants. This is because some plants require more water than others. Therefore, an appropriate water amount for one plant may be over-watering for another.
• Choosing the right soil: Different soil types have different drainage degrees. For example, though clay soil is the best at retaining water, it has very poor drainage. Sandy soil on the other hand is very well-drained but poor at retaining water. The type of soil you use depends on the plant. Don’t just assume that sand soil works for every plant.
• Providing sufficient drainage: Indoor plants such as money trees should be drained appropriately to prevent water from adding up and congesting the roots.⁴ Drainage is determined by container and soil type. Experts recommend planting a houseplant in a container that has a drainage hole which will allow excess water to drain from the soil when the plant is watered. Most decorative planters do not come with drainage holes. For this reason, you can place the plant in a smaller nursery pot made of plastic and stick it inside the decorative planter. When you want to water the plant, all you have to do is remove the pot before watering to facilitate drainage of excess water then put it back into the decorative planter until the next watering session.
• Keeping a regular watering schedule: Most plants thrive with a regular watering schedule. Sporadic watering will shock and injure the roots. It might also mean that the roots do not dry between watering sessions and this will lead to plant rot.

#2 Check and Aerate the Soil

You must check and aerate the soil regularly to ensure that the plant lives a long life. Aerating the soil has many benefits such as:¹¹

• Loosening up the soil
• Allowing even water distribution
• Promoting oxygen flow
• Preventing moisture build-up

You must also check the moisture content of the soil before watering your plant. If the soil is moist an inch or two from the surface, then it’s over-saturated with water.⁵

You may need to skip that watering session or replace the soil in the pot.

The best way of preventing root rot is avoiding overwatering, checking and aerating the soil, and watching out for symptoms to ensure that your houseplants are healthy.

Frequently Asked Questions About Root Rot