Spider plants are low-maintenance, which makes them good starter plants for novice gardeners. One of the most common conditions to affect spider plants is root rot, and the most common cause of this is overwatering. When there is too much moisture in the soil around the plant’s roots, the roots will suffocate and start to die. Once dead, they become susceptible to opportunistic pathogens that cause root rot.
In this article, we will discuss the most common causes of root rot in spider plants and how you can remedy it.
How do I know if my spider plant has root rot?
One of the first signs you will notice if your spider plant has root rot is a foul odor emanating from the plant’s roots. The smell is similar to that of rotting vegetation.
This is due to the rotten roots, which have been affected by bacteria for some time already.
If you notice this distinct smell, you should suspect root rot and take the proper steps to diagnose the condition and start treatment.
Mushy, brown or black roots
The most telling sign of root rot is when the roots have turned brown or black and are soft and mushy.
The roots are the first parts of the plant to be affected by the fungus, but unless you are repotting your plants, you cannot really tell whether roots are damaged.
If other symptoms have led you to suspect root rot, you may have to uproot your plant to check the roots and confirm your suspicions.
Another sign your spider plant has root rot is if its growth has been stunted for weeks, or even months.
Effects on the plant’s foliage may not appear immediately, but when the plant no longer grows new leaves, it may be due to root rot.
Wilted leaves are not a sign specific to root rot, but it is a sign that the plant is experiencing some type of stress that needs addressing.
When the plant’s roots are damaged, they are unable to absorb water and nutrients properly, and this will have an effect on the plant as a whole, including its leaves.
The presence of black spots on the plant means that the rot has moved upward significantly and is now affecting more than just the roots. The pathogens that are causing the rot are aggressively taking over the entire plant and it might be too late to salvage it.
What causes root rot in spider plants?
The most common cause of root rot is simply giving the plant more water than it needs. It may be because you are giving the plant too much water each time, or you could be giving it the correct amount too frequently.
Both scenarios can cause the soil to become waterlogged and soggy for long periods, and the roots will not be able to dry out between waterings.
You will also notice the plant’s leaves turning yellow or brown and becoming droopy if you have been overwatering it.
Because there is always water present in the soil, the roots will be unable to breathe, and that will affect the flow of nutrients and water from the soil to the plant.
To know when you should water your plant, touch the soil to feel if it is dry. If it is dry, water the plant, but if the soil is still damp, wait a few days before checking it again.
2. Poorly-draining soil
Another reason your spider plant may have root rot is if the soil in its pot does not drain well.
These plants need well-draining soil so that it can be properly aerated. The soil should allow both water and air to flow through freely.
When the soil you use is heavy and compacted, such as clay, it holds onto moisture too well and does not dry out fast enough.
Even if you have good watering techniques, if the soil is poorly-draining your plant will still be at risk of root rot.
3. Cold temperatures
When the temperatures around your plant go below 50 degrees Fahrenheit, this can also lead to root rot.
Low temperatures mean that the soil around the plant’s roots will not be able to dry out as quickly as in normal temperatures.
This is especially true for plants that are kept in places that do not get much light. Sunlight can help regulate the temperature around the plant which helps the soil to dry out, so in the absence of sunlight, the plant can also show symptoms of overwatering.
4. The pot has no drainage holes
If the pot you use for your spider plant does not have drainage holes at the bottom, this keeps water trapped in the soil and around the roots.
You can use a pot without drainage holes, but that requires you to make no mistakes when it comes to watering your plant; the amount of water you give should be exactly right.
Even if the pot has drainage holes, they can become clogged with soil or pebbles, so make sure you check these holes regularly.
Spider plants are light feeders so there is no need to fertilize them that often, if at all. The nutrients found in rich potting soil are usually enough for them to stay healthy.
If you overfeed your spider plant, it can lead to a mineral buildup that is not good for the plant, and the roots will become weak and vulnerable to root rot.
The most common species of fungi that cause root rot in spider plants are the Pythium, Phytophthora and Rhizoctonia species. They all attack vulnerable roots, usually brought about by overwatering.
These pathogens are spread through contaminated soil or contaminated gardening tools such as shears and spades. Make sure you do not reuse soil from a contaminated plant; you are better off discarding it and using fresh soil.
Can a spider plant with root rot be salvaged?
Yes, if the root rot has only affected some of the roots and the majority are still white and healthy, the plant is salvageable.
Cut off the brown or black roots using sterile scissors and spray some fungicide on the healthy roots. Let the plant air-dry for a day before replanting it in a pot with drainage holes, using fresh potting soil.
Spider plant root rot most commonly occurs when the plant is being overwatered or overfed. When the plant is given too much water or fertilizer, the roots will weaken and become vulnerable to opportunistic pathogens which then cause root rot.
The rot will travel up the plant until it affects it entirely, and it will eventually die.
Prevent root rot by making sure you do not overwater or overfeed the plant, and use well-draining soil and a pot with drainage holes. Use sterile tools when handling the plant to avoid infecting other plants.
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