7 Moth Orchid Mistakes to Avoid This Season

Moth orchids, which go by the botanical name Phalaenopsis, are the most popular orchids to keep as houseplants. Of 850 genera, the Phalaenopsis genus is the most widely propagated and sold worldwide. There is a simple and sensible reason for this. They are the easiest to care for in the home environment. 

Moth orchids are sturdy, with substantial leaves and root systems. Their care is straightforward, and while some genera have very specific needs, this one can handle a bit more neglect. Its hardy roots resist root rot more than most, and that is the number one killer of these plants. 

If you want your moth orchid to live up to its full potential, there are some key mistakes to avoid. Let’s dig in and talk about things you should and should not do to give your Phalaenopsis a healthy and robust season. 

Overwatering

The top killers of moth orchids are watering mistakes that lead to root rot. These epiphytes have highly sensitive roots that are adapted to a certain lifestyle. In the wild, these plants grow on trees rather than in soil. Their exposed roots receive an abundance of rain and have plenty of air circulation. 

This is why it’s so important to hone your watering practices to their specific needs. Indoors, your plant will only need water about once per week. If you keep the potting media wet, it will begin to decay, and an orchid’s sensitive roots can’t tolerate that. Overwatering causes the exterior of the roots to break down, and fungus infiltrates them. 

When fungus gets into the roots of your plant, it further breaks them down. This inhibits its ability to take in water and nutrients. Essentially, it starves the plant. Root rot is difficult to diagnose until it’s a problem unless your plant has exposed roots. By the time it’s obvious that the rest of the plant is suffering, it’s may be too late. 

Water only once per week and slightly less in the winter. When the orchid is not in a growth phase, it will need less moisture. Allow the potting media to dry between waterings.

I prefer to water by immersing the pot in a bucket or sink full of water. Leaving it in the water for a few minutes allows the roots to absorb what they need. As long as you pot it properly, this will be an effective approach.

Using the Wrong Potting Mix

Another way to ward off the dreaded root rot is to use the right type of potting media. Because these plants grow on trees rather than in soil, they have different soil needs. If you use regular potting soil, you’ll almost certainly suffocate the roots and end up with root rot. 

Instead of potting soil, use a mixture of large and coarse particles or a commercially made bark mix. Usually, these are a combination of bark, pumice, charcoal, perlite, and peat, or any combination of these. These particles give the roots something to anchor to, but they also allow water to flow freely through. 

Using the Wrong Container

You’re probably getting tired of all this root talk by now, but it doesn’t end quite yet. Orchids’ roots are such an important factor in their care. Any orchid enthusiast who’s been at it awhile has at least one sad root rot story. Another important factor in maintaining that all-important part is the container. 

Your orchid needs excellent drainage, and the pot is the most important factor in drainage. If you put an orchid in a pot without drainage, it will almost certainly rot. 

I’m sure there are a few stories out there of people doing it. Maybe they got the orchid as a gift and left it in the plastic pot inside another pot with no drainage. Perhaps they only use ice cubes to water it, and it blooms three times a year. Even if you make these mistakes with a moth orchid, they may still survive. That is why they are so popular—they are sturdy!

But just because it could work out that way is never enough reason for me to take the chance. I always re-pot my orchids as soon as they finish blooming. Three kinds of pots work well for this purpose. 

1. Wooden orchid baskets or wood mounts: These are great for outdoor orchids and do a wonderful job of mimicking the plant’s natural habits. However, they can be messy indoors, as the potting mix and water will drop through the slats. 

2. Ceramic orchid pots: These are the most decorative, with holes in the sides typically arranged in a pattern. They work well, but they don’t breathe, so it’s slightly easier to overwater them. They are the prettiest, though, so it’s a trade-off for me.

3. Terracotta pots: These are standard clay pots, but they have extra drainage holes. They are sturdy, wick water away from the roots, and have excellent drainage. Although they have a more rustic appearance than ceramic, I still favor them. 

Incorrect Fertilizing

Since your plant is dormant during the winter months, don’t give it as much fertilizer and water. We talked about water, now let’s go over how to properly fertilize your orchid throughout the year. 

When your plant is growing, you should fertilize once every other week. Because the moisture doesn’t soak into the potting media well, it runs out quickly. It’s better to fertilize more often with a diluted formula. I prefer to immerse my orchids to water them, and it’s a cinch to add a bit of fertilizer to the water every other week. 

Most orchids enter dormancy in the winter. This can last several months, and during this time, they need reduced care. Less water will prevent root rot, but what about fertilizer? If you fertilize while a plant is dormant, it won’t absorb the nutrients, and the roots can burn. This leads to other issues and can do significant damage. 

Suspend fertilizing until spring, and if you suspect a buildup in the roots, give them a good rinse with clean water. This will help flush out excess salts that can burn them. 

Low Humidity

Orchids need a lot of humidity. Phalaenopsis is happy with 40-60%, which is not difficult to achieve in most homes. However, running the heat in winter can dry out the air. If you notice that you’re going through moisturizer faster than usual, your orchid probably needs more moisture, too.

I favor the bathroom as a good spot for mine. They seem happy there with the extra humidity. If you have yours in a common area of the home, think about running a humidifier for the cold months. Your Phalaenopsis with thank you, and so will your skin!

Not Enough Light

These epiphytes love dappled or filtered sun. While they are usually happy with medium to bright indirect light, in winter, the daylight hours get shorter. Moving your plant just a bit closer to the light source will make up for the difference. 

It’s difficult to tell in the short term if your orchid is getting enough light, particularly while it’s dormant. The growth slows during this time and growth is the method of determining light needs. If you’re getting lots of dark green growth but no flowers, you need more light. 

The leaves of a Phalaenopsis are large, glossy, and dark green. In other species, the leaves will be lighter green in the right exposure and darker with too little light. This species is different. An absence of flowers for a year is a good indication if there are no other visible issues.

Too Much Light

It’s a much easier mistake to give a moth orchid too much sun than too little. These really don’t like or need any direct sunlight. There should always be a filter of some sort if the light shines directly on them. 

A Phalaenopsis will certainly let you know if it’s getting too much sun. Just like us, they will get sunburned. If you see faded spots on the tops of leaves, move it away from that window a bit. These faded spots don’t go away, and if it progresses too much, the leaf will burn and start to rot, and you’ll have to remove it. No one wants that!