How to Fix Root Rot in Orchid Plants

Orchids are a wonderful and fascinating family of plants. They enchant with their stunning, colorful, and often fragrant flowers. They do, however, require quite a bit of attention when kept as houseplants, and it can take some experimenting to strike the right balance of care.

If you talk to most orchid enthusiasts, you will hear a similar story about an experience they had early on in caring for orchids. It is something most of us have encountered along the way, and some of us more than once. The biggest issue in caring for orchids, particularly indoors, is one that plagues even the most experienced houseplant enthusiasts at times.

Root rot is the result of an orchid’s roots being exposed to more water than they can absorb. This can happen as a result of a handful of elements, all of which are within the control of the gardener. But sometimes raising orchids takes a bit of trial and error. Ironically, this is especially true of gardeners who spend a lot of time caring for their plants.

Overwatering is the number one cause of root rot. An orchid’s roots can only take in just so much water before they start to weaken and break down, creating an environment for bacteria and fungus to creep in.

It is fungus that causes root rot, and water is fungi’s best friend. Most indoor orchids need only to be watered once per week at the most, and they thrive on a bit of neglect in terms of watering.

In addition to overwatering, the wrong potting soil, or the wrong type of pot can also be a cause of root rot. When growing in nature, orchids mainly grow on the trunks and limbs of trees. In other words, their roots are not buried in soil, but rather, they are exposed to the air.

Given this fact, it is important to pot an orchid properly, in such a way that its roots have proper air circulation, which enables them to dry out in between waterings.

 Using a proper potting medium is another factor which is vital to plant health. The right potting medium is one part of the potting quandary, the other is the type of container or pot.

If you have these three factors in order; container, potting medium, and watering, you are almost assured that your orchid won’t fall prey to the dreaded root rot.

But as I said, sometimes it takes a little trial and error to get a feel for proper maintenance, and the best of intentions don’t always translate the way we hope, so if you find yourself in the position of having an orchid with root rot, read on.

The Diagnosis

The all-important question is, how do I know if my orchid is suffering from root rot, or some other pest or pestilence? If you can’t see the roots, it can be difficult to know that the plant is suffering from root rot until it has progressed, and the foliage is affected.

Once the issue has reached the leaves, they will begin to yellow and fall off. At this stage, it is very difficult to bring the orchid back to health.

The best way to catch root rot early on is to poke a bit into the potting medium, so that you can get a look at the roots. Their roots can tell you everything you need to know about its health relative to watering.

What Do Healthy Roots Look Like?

Healthy roots are generally green to white, plump, and somewhat flexible. The surface of the roots should be relatively smooth and not pitted. All orchid roots are not identical, a phalaenopsis orchid should have thick, green, snaking roots.

Cattleya orchids will have a mass of white roots that connect to each of its pseudobulbs. Dendrobium’s roots are green nearest the plant and generally a tangle of white beneath. The most important factor is that they are mostly smooth and green or white in color.

In general, if the roots are plump and white, and appear to be producing new growth, they are healthy, and your watering practices are working.

If your roots are healthy and the plant is still looking sickly, the culprit is more likely to be insects which love to feast on orchids’ sweet sap. Insects like aphids, mealybugs, and thrips all love to munch on orchids.

What Do Rotten Roots Look Like?

Rotten roots are pretty similar across the board. They are dark brown to black, and mushy. When the rot is advanced, they will basically fall apart in your hands in a squishy brown mess.

In less advanced cases you might notice a darkening of the roots and some irregularities where they have begun to deteriorate, rather than the smooth surface of healthy roots.

Once an orchid’s roots (or other parts of the plant) have begun to rot, there is no saving that portion of the plant. If left intact, the fungus will continue to spread and affect other tissue.

What Do Dry Roots Look Like?

Since we are on the topic of roots and what they should look like, it’s worthwhile to spend a moment on dry roots. If an orchid is not getting enough water its roots will turn a sickly gray and have a crackled appearance. Dry roots may appear wrinkled and dehydrated. This is a much simpler problem to fix, as a good watering should plump up those roots quickly.

White dry roots may be similar in color to healthy roots, their texture will be different. It is important to make this distinction because, well, you don’t want to overwater.

The Fix

Bringing an orchid back from an advanced case of root rot is not for the faint of heart. It is, at best, an effort that may be worth attempting. But in the words of every mother whose child has interceded with Santa Claus for a puppy, don’t get your hopes up. That way, if it works, you will be pleasantly surprised.

If, however, you have managed to catch your root problems early, there are some valuable steps you can take to help put your orchid back on the road to good health. The key is to address the issue right away, to preserve as much healthy tissue as possible. The steps to this process are very similar to repotting an orchid.

First, remove the plant from its container and gently shake all bits of potting medium from the roots. Compromised roots are fragile, so do this with care not to break off as much as possible, you want your cuts to be as clean as possible, clean cuts heal faster.

Removing any potting mix that has been affected by fungus is important, you don’t want to reintroduce the same fungus back into the freshly trimmed roots.

Next, using a sharp, sterile tool, trim away the damaged portions of the roots. Anything that looks dark, mushy, or deflated should go. Take care to preserve any healthy roots that are left, as your plant will need these to help it make a comeback.

 After trimming away the diseased portions of root, treat the remaining healthy roots with an antifungal, anti-bacterial agent such as a copper-based fungicide. Skip over other controversial methods like using ground cinnamon, or hydrogen peroxide.

Powdered sulfur is a good treatment as well but use it very sparingly as it will desiccate the roots if you use too much. It might be good for treating minor cuts on a healthy orchid, but will be a bit severe for this purpose.

Finally, repot the orchid. The best containers have plenty of drainage and holes in both the sides and bottom for air circulation. Terracotta pots are wonderful because they wick water away from the roots, but retain a bit in themselves, so they strike a good balance.

If you can tolerate the mess they tend to cause, wooden baskets are a great option, as they provide maximum drainage and a situation most alike to the orchid’s natural habitat. It can be difficult to keep these indoors, as they tend to shed bits of potting medium with any jostling.

Also, of great importance in potting is the material used as a potting medium. Orchids can’t be potted in regular potting soil; It holds far too much moisture.  They need a special mixture of large particles that drain well and allow for good airflow around the roots.

Commercial potting mix works great, and it is easy to find. If you prefer to make your own mixture, a good recipe is 60% orchid bark, and the remaining 40% should be a combination of charcoal, perlite and sponge rock or pumice.

The Extended Fix

Once you have dealt with the immediate problem of rotting roots, it is important to make some adjustments in your care routine to avoid a relapse. Here is a brief overview of good care practices to achieve a healthy and thriving plant.

Watering

Most indoor orchids are happy to be watered once per week. There are several watering methods that work, and most of them are effective if carried out on a proper schedule.

It’s a good idea with orchids to have a specific watering day, so that you don’t accidentally overwater. The most important factor is drainage. If your drainage is good, you have a much better chance of avoiding a relapse.

Fertilizer

Orchids enjoy being fertilized. During their growing and blooming seasons, you can fertilize your orchid once per week and it will absolutely love you for it. After the blooms fall and the plant is dormant, you can reduce fertilizing to once every 3 weeks.

There are lots of commercially available fertilizers made just for orchids. These are fabulous, but if you don’t want to invest in a fertilizer for one specific plant, an all-purpose, balanced fertilizer, diluted to half strength, is just fine as well.

Humidity and Air Circulation

These 2 factors are also important in maintaining a healthy environment for your orchid. Orchids like a lot of humidity. The percentage varies by genera, but in general, they prefer humidity levels of between 40%-70%.

A bathroom window is a great spot for an orchid. If you don’t have one of those, a humidifier will help raise the humidity level in your orchid’s space. A dish of water placed beneath the pot will also provide extra humidity. As the water evaporates it will give your orchid an extra boost. Just make sure not to let your orchid’s roots sit in water, or the problems will start all over again.

Air circulation is the final piece of the puzzle. Orchids need a lot of air around their roots. With all that humidity in the air, it’s a good idea to keep it moving. A fan, air purifier or vent fan are all adequate for this purpose.