Phalaenopsis orchids are the most common variety of orchid to be kept at home. Thankfully they have relatively low light requirements compared to other species of orchid. But the amount of light that they get makes a big difference to how well they thrive. This article will tell you exactly how much light phalaenopsis orchids need, and how to identify and fix any problems.
How much light do phalaenopsis orchids need? Phalaenopsis orchids need bright but indirect light and are best placed in an east or west facing window. Avoid exposing your orchid to more than 1 to 2 hours of direct sunlight per day. Pale leaves with brown patches indicate excessive light. Dark green leaves indicate insufficient lighting.
Phalaenopsis orchids typically grow beneath the tree canopy in forests and are not used to getting much if any direct sunlight, as little makes it through the canopy of the forest. As a result, they have adapted to low light conditions, which is fortunate for us, as our homes typically have lighting conditions not dissimilar to a forest floor.
Phalaenopsis Orchid Positioning
To get the perfect amount of light for your phalaenopsis orchid, place it in an east or west facing window. Putting your orchids in the middle of a room far from a window, or in a north facing window will typically not provide sufficient light to let it thrive.
Excessive direct sunlight in a south-facing window or positioning your orchid where it gets more than 1 to 2 hours of direct sunlight per day will typically lead to problems with excessive sunlight.
Phalaenopsis orchids can be quite adaptable, and whilst ideal light conditions will help the plant to thrive, they can often survive quite well for short periods of time in less than ideal light conditions.
Interestingly, excessive lighting can at first seem to help phalaenopsis orchids, as the additional light gives them the energy to produce more blooms, more frequently. However, the damage done by excessive lighting will take its toll over time, and eventually, this will lead to damage to the plant.
Light conditions often vary dramatically depending on the distance your orchid is from a window. A south-facing windowsill can get almost 10 times as much light as a position just a few feet away from the window. Just moving your orchid from directly beside a window, to a nearby table may be all that is required to fine tune the lighting to perfection.
How To Check How Much Light My Orchid Is Getting
There are a few different ways to check how much light your orchid is receiving. If you want to assess whether you have got your orchid in the right place, check the light levels on a bright and sunny day. Here are the two best ways to check light levels.
- The simplest way to measure light levels is to measure the amount of shadow that falls on the leaves of your orchid. Hold your hand about 12 inches away from the orchid and try to cast a shadow on the Leaves. Ideally, you should only see a faint and irregular shadow forming on the Leaves. If you see a well defined, black shadow, this indicates bright light conditions and is excessive for your phalaenopsis orchid. This should prompt you to move your orchid to a better location. Alternatively, you can use a lux meter, which can give you a very precise measure of the light that your plants are receiving. Lux meters are actually very affordable, so if you have quite a number of plants, or are struggling with the care of your orchids, it is well worth getting one.
Phalaenopsis Orchid Lux Requirements
Lux is the scientific measure of the intensity of light that hits a surface, measured in lumens per square meter. Ideally, phalaenopsis orchids should get about 10700 to 16000 lux for at least 8 hours per day, for optimal growing.
They will tolerate much lower light conditions for a long time, but may not thrive. Prolonged higher lighting levels will lead to damage to the foliage, which can be easily identified and reacted to. Phalaenopsis orchids are ideal for growing in indoor conditions, where lighting conditions are generally much lower than those outside.
Orchid Light Problems
The great thing about phalaenopsis orchids is that you can monitor lighting conditions by observing the leaves. I’m going to discuss exactly how to assess the lighting of your orchid, identify problems and resolve them quickly.
Phalaenopsis Orchid Excessive Light Problems
If your phalaenopsis orchid is getting too much light, the first place to look is the leaves. They will start to become paler in color and can take on a yellow appearance with prolonged excessive light conditions. They can also develop pale reddish spots around the edges of the leaves which can be easily identified on inspection.
With prolonged and intense direct sunlight, the leaves of your phalaenopsis orchid will also develop brown tips or edges. They can also become wrinkled due to the very low humidity conditions that this will produce.
Of course, excessive light isn’t the only reason a phalaenopsis orchid will get yellow leaves. So read more here about the other causes of why orchids get yellow leaves.
Interestingly, I have tried placing phalaenopsis orchids in direct sunlight during the summer. Although this eventually caused significant harm to the plant, it initially helped blooming. In particular, it increased the rate of reblooming from the same flower spike.
However, don’t be tempted to do this, as the damage to your phalaenopsis orchid will be quite significant. The excessive direct sunlight will do often cause irrepairable damage to the leaves.
So if you see direct sunlight on your orchid for more than 1 to 2 hours per day, move the orchid to a different location. They will typically be able to tolerate some early morning direct sunlight in an east-facing window, or late evening direct sunlight in a west-facing window. But the direct sunlight in the middle of the day from a south-facing window will simply be too intense and will damage your orchid.
If you really want to keep your orchid in a south-facing window, sheer curtains can reduce the intensity of the sunlight, or you could place another barrier in front of your orchid to shield it from direct sunlight.
Problems With Too Little Light For Phalaenopsis Orchids
Low light conditions can be more difficult to identify, as the leaves will often look extremely healthy and vibrant. They will become a darker and richer green color, as the leaves try to produce more chlorophyll to maximize the use of the scarce light available.
However, this is a sign that your phalaenopsis orchid is struggling. An orchid that is kept in low light lighting conditions is very unlikely to produce new blooms. If you are having trouble getting your phalaenopsis orchid to rebloom, definitely consider lighting as a cause of the issue.
You need some caution when moving an orchid from low light conditions to higher light conditions. It will take them a while to acclimatize to higher light levels. Suddenly moving a phalaenopsis from a dark room to a south facing window, can cause sunburn. It’s better to move it to a location with moderate light levels first for a few days. Then you can move it to the location you have identified with perfect light conditions.
Growing Orchids Under Led Lights
It is possible to grow orchids under grow lights, but not usually necessary unless you have limited light conditions. If you are trying to grow a phalaenopsis orchid in a dark room, LED or fluorescent grow lights are best due to their low heat output and high efficiency. You should set them up to provide 11000 to 16000 lux for 8 to 12 hours per day.
Do Orchids Need Light On Their Roots?
Phalaenopsis orchids have green roots, which is a characteristic that is unusual to most other plants. The reason for this is that phalaenopsis orchids are epiphytic plants. They grow attached to trees rather than in soil.
As the roots are exposed to light, orchids have adapted to this and produce chlorophyll in the roots. This can contribute to photosynthesis and energy generation for the plant. Whilst it is generally best practice to expose phalaenopsis orchid roots to light, it is not completely necessary. Your orchid will thrive as long as the leaves are receiving good levels of sunlight.
Generally though, I would recommend placing your orchid in a very loose potting medium in a transparent pot. This allows the roots some light exposure to help the plant increase its ability to thrive and bloom. Read my article on how to repot orchids for more information.