Unhealthy Orchid Roots – Signs and What To Do

Unhealthy Orchid Roots - Signs and What To Do

You can tell a lot about an orchid’s conditions by simply looking at its roots. When an orchid’s roots are brittle and dry, the plant is being underwatered, but when the roots are mushy and brown, it is being overwatered and has root rot. Diseases brought about by pathogens can also target orchid roots and cause problems.

Having unhealthy roots is not always a death sentence for your orchid, and there are many ways you can salvage the plant.

In this article, we will discuss the different signs to watch out for in order to identify unhealthy roots, and what one should do to remedy the problem.

If you suspect that your orchids have unhealthy roots and you want to learn more, just keep reading.

What do orchid roots do for the plant?

Before we dive into the signs of unhealthy orchid roots, let us first discuss why it is so important to care for your orchid’s roots.

Orchid roots store extra nutrients and minerals for the plant. The roots can literally become a storage cellar of food for the plant, which it can use up when nutrients in the environment are scarce.

Roots also help anchor the plant onto its potting medium. This helps keep it in place so that, even if it is not grown in soil, it is still able to remain steady.

The most important job of orchid roots is the absorption of the water and minerals that the plant needs to survive. If the roots are defective, the orchid will not be able to hydrate and feed itself. Because orchids are epiphytic, their roots are able to absorb all they need directly from the air around them. 

Thus, keeping an orchid’s roots healthy is important to keep the whole plant healthy.

Healthy vs. unhealthy orchid roots

Healthy orchid roots are white or green in color. They are not always bright green, but become so just after they are watered. You should note that the roots are only bright green after watering and that they are not supposed to be bright green at all times. Healthy roots are firm when you touch them. 

Unhealthy orchid roots can either look brown and feel soft and mushy, or they can be dry and brittle. Orchid roots that are always bright green may also be a sign of overwatering.

What are the common diseases of orchid roots?

1. Fungal diseases

When you see yellow or pink growth on the orchid’s roots, this is most probably due to fungi. Fungal diseases can become rampant if the roots are left to stand in water for long periods of time.

Mold grows on orchid roots when the climate is humid or hot. Molds love moisture, so being a little too enthusiastic with watering or misting can also have its downsides.

Placing the plant near a source of warm air, such as an air conditioner, can also cause mold to grow. It is possible that it started to grow while still in the flower shop, but has only become apparent after bringing the plant home.

Look for white mold on the roots, especially if you are prone to overzealous watering. If the potting medium is constantly wet, white fungus will grow on the roots and in the potting medium itself.

You can prevent the growth of mold by making sure that the potting medium is well-draining and aerated.

Blue mold also appears in humid conditions and after too much watering. The spores may already be present in the bark where the orchids are grown.

Snow fungus also likes moist environments and looks like white balls that appear on the potting medium. Fortunately, this fungus does not do much harm to the orchid, but it will drain some of the nutrients from the potting medium. Change the potting medium and spray the roots with fungicide to protect them. 

Reduce your watering frequency to discourage the growth of mold and fungi. Prevent fungal diseases in orchid roots by making sure the plant’s pot or container is well-draining. Try not to expose the plant to sudden temperature changes, because this can lead to fungal colonies on the roots and on the potting medium. Make sure the potting medium is airy and loose so that oxygen can flow through it freely.

You can also water the roots with a citric acid solution once every two weeks. Add half a teaspoon of citric acid to a glass of water and use that to water the plant.

Another trick is to place dry orange peels on the surface of the potting medium to keep the spores of any fungi from penetrating the substrate.

Some people also swear by the use of garlic to rid the potting medium of fungi.

2. Bacterial diseases

When an orchid’s roots are infected by bacteria, they will have ulcerations and they will soften. These soft parts are rotten and will need to be removed as soon as possible. Cut off the infected roots to prevent further spread of the disease. Make sure you use sterilized pruning shears to do this.

You can tell that your orchid has a bacterial infection if the leaves and the roots both look darker than normal. Bacteria can also cause the roots to rot, and spots to appear on the leaves.

Bacterial infections are more likely to occur when humidity and room temperature are high, and when there is lots of moisture. Bacterial infections can spread from one plant to another if the first infected plant is not separated from the others in time. The orchids can also be infected by unclean water, especially if they are being watered at the same time from the same source.

Another way that orchids become infected with bacteria is through disease-carrying insects.

Bacterial diseases can be treatable, but the sooner the disease is identified, the better the chances of recovery for the plant.

Remember to keep the plant away from your other plants while you are treating it in order to control the spread. 

3. Viral diseases

When you see spots and stripes appearing on the roots, this could be due to a viral infection. The entire plant will be affected. Unfortunately, viral diseases in orchids are rarely treatable, so you are better off destroying the plant and disposing of it properly. This is the best thing to do, rather than risk the rapid spread of the virus across all of your plants.

Why are my orchid’s roots turning black?

There are different reasons your orchid’s roots might turn black. These include old age, bacteria, fungi, overwatering or insufficient light.

Why are there spots on the roots of my orchid?

As mentioned above, this can be due to a viral infection, but it can also be a fungal infection. 

Why is the base of my orchid black?

If the orchid is kept in a dark room, it will rot at the base. Because orchids are inherently tropical plants, they do not like cold temperatures, so refrain from keeping your orchid in places with low temperatures.

Why are the tips of my orchid’s roots black?

Orchid roots turn black and become dry at the tips when you overfeed them, when the fertilizer is too concentrated, or when you constantly use hard water when watering the orchid.

You can try to remedy this by flushing out as much fertilizer as possible under a stream of warm water. You should do this several times, making sure to let any excess water drip out so that the plant is not overwatered.

Why are the roots of my orchid dry?

When your orchid does not get enough water, the roots will dry out and even die. This happens more easily in hot, dry climates.

The drying out of the roots can also be due to the plant’s natural aging process, so you do not need to always assume the worst. Roots, like leaves and blooms, also only exist for a certain amount of time and will die at some point. These roots often last only between two to three years. When the old roots die and fall off, the plant will grow new, young roots to replace them.

You may need to transplant your orchid every two years or so, and at the same time you can also remove any dead roots. This way, you can keep the plant healthy and maintain its overall aesthetic.


Unhealthy orchid roots are either brown and mushy, dry and brittle, black at the tips, or have white spots on them.

Healthy roots are white, becoming bright green only when they have recently been watered.

In order to keep an orchid’s roots healthy, you need to be vigilant with your watering routine. Do not let any of the roots come into contact with stagnant water, and make sure the orchid’s pot and potting medium are well-draining and aerated.

The potting medium should be able to dry out between waterings, and the plant should get plenty of bright, indirect light. Be on the lookout for pests and diseases so you can treat the plant in the early stages of any infection.

As long as you provide an orchid with its most basic cultural needs and protect it from infections or infestations, it can live to be several decades old.

Image: istockphoto.com / alexytrener