Q & A: Why Are My Orchid Leaves
One common problem with orchid is the leaves turning brown. This is a sign that there is an underlying problem that needs to be fixed before it continues to damage the rest of the orchid. In this article, you’ll learn the 6 most common reasons the leaves on your orchid will turn brown and how to fix each problem. Read through each one of these causes to see what could be ailing your orchid’s leaves.
Orchid leaves turn brown due to dehydration, bacterial brown spot, severe sunburn, salt build-up, fertilizer deficiency, and inadequate relative humidity. The molting of a healthy green color quickly fades into a dark brown, revealing several unnatural problems. Fortunately, all 6 "brown-leaf" complications are all easy to fix.
Before you dive into reading what is the actual problem for your orchid’s leaves to turn brown, not the following signs:
1) Where does the leaf start to turn brown? Is it in the middle of the leaf or on the sides?
2) Are the older leaves turning brown or just the newer leaves? Are all the leaves turning brown? Which leaves turn brown is a clear sign of where to look for the culprit.
3) Are the sides of the orchid leaf turning brown or is it the whole leaf? The sides of the leaf are easily curable, but if it’s the whole leaf, the problem is a little bit bigger.
Once you have noted the answers to those three questions, you can easily identify the culprit.
"Refreshment to my Senses" by LadyDragonflyCC - >;< is licensed under CC BY 2.0
1) Orchid Leaves Turn Brown Due to Dehydration
When the orchid can’t get access to water, the leaves are the first to note the difference. Just like a sunflower in the middle of a field without rain for several days (and yes, since I’m from Kansas my illustrations are all rural) the leaves will start to fade and crumble. Before they fall off, the leaves will turn a dusty brown color.
The same is true of orchid and any plant for that matter. When there is a lack of water the orchid leaves will turn brown. To know that it is in fact a lack of water, the entire leaf will start to turn brown. It will not just be the sides or leaf tips.
Before it turns brown, it will become leathery and limp. The appearance will be of deep wrinkles and grooves in the orchid, like creases in a lifeless, floppy leaf.
The picture below show signs of a severely dehydrated orchid leaf. In time, it will turn brown. Healthy orchid leaves will be smooth, firm, light green to medium green, and shinny.
Image Credit: © 2020 Orchideria. All Rights Reserved.
Both the newer and the older leaves will show signs, indistinctly. When there is a watering problem, there is not one leaf that will benefit from the others, such as in a fertilizer deficiency. All leaves will equally brown on your orchid.
The underlying problem with the lack of water is that in most simple solutions, we’d just water more. I wish that were the case, but it’s not.
Sometimes too much water has made the orchid roots rot away, leaving behind not roots to absorb the water. Other times the roots have encountered a problem and died off, therefore the orchid has no way of absorbing the water you provide it.
Don’t assume that lack of water can be solved by watering more.
Unpot your orchid. Check the roots and the health status of the stem. Are the roots green, plump, thick, resistant to pressure (squeeze them between your fingers), and have green root tips? If yes, then the problem is not water abortion as in poor roots. It might be a lack of water though—increase the times you water and how long you give them water.
If your orchid roots are mushy, brown, soggy, lifeless, and do not hold their shape, then your compacted potting medium is not letting your orchid drink water. Check for sufficient water drainage. To do this, take your orchid to the sink and run water through it.
It should exit as soon as you turn the water on, with a quick flush of the pot. If the water backs up and pools on the top of the potting medium, your media is too compact.
There is no air, either. This would also cause the water to have a hard time traveling through the pot and coming in contact with the roots. Soon your orchid roots will die from this tightly compacted media.
Either way, you need to provide more ways to water your orchid. Either water more frequently or water with more water (quantity) given you have healthy roots. The brown tips on the orchid leaf will not recover and forever be a sign of being poorly watered.
Orchids hold grudges in this sense. Only when the leaf falls off will that reminder that inadequate care was provided. Oh well… At least you got your orchid back to life and it is now on its way to a healthier lifestyle.
2) Orchid Leaves Turn Brown Due to Bacterial Brown Spot
If your orchid leaf is not browning all the same but just in some specific spots, like pencil eraser dots, or splatters of paint, then you might not be dealing with a lack of roots but a bacterial infection.
In Bacterial Brown Spot, the lesion starts off as a tiny, minuscule dot that paints the top of the leaf.
This could be due to overmisting, while the water sits on top of the leaf. Without airflow, the water destroys the top of the plant cells, and that tissue dies where the water made it impossible to perform gas exchange.
In a Phalaenopsis, the orchid leaves are hydro-repellent, which means water will roll off the top of the leaf onto the forest floor under it. Yet in our home environments, sitting in an unnatural position in the pot, the water droplets have nowhere to roll off the leaf.
The water sits there indefinitely, which is why it is so important to have airflow at all times. If you don’t have a fan, then this would be a good time to get one. Even small computer fans can do the trick when the orchid shelf is small.
The sitting, stale water sits on the orchid leaf and kills the outer cell layer. This breaks down the protective coating that the orchid has against bacteria, fungus, and viruses. (Viruses are usually transmitted through nonsterile pruners or scissors, not through the tears in the leaf. Yet they can be, so don’t rule out this possibility.)
The bacterial infection that is most common causes brown spots to grow, sinking in the leaf. Where the water droplet was once on the leaf, now is a thin sunken valley that looks water-logged. I wrote a whole article on Bacterial Brown Spot, so I won’t repeat it all here. You can read that article here
and how to cure it.
3) Orchid Leaves Turn Brown Due to Severe Sunburn
If your orchid as been sitting in an east-facing window and getting morning sun for quite some time, it should be happy. Problems occur when we want to take these orchids outside and place them in a position that isn’t common for them.
Just like going out into the sun without sunscreen, orchid leaves burn. This can happen from one day to the next. The patches of the sunburnt leaf will appear pale-yellow then slowly turn white. Over time they can turn brown or black.
The top leaves will show these signs but not the lower, older leaves. Anywhere the sun hits, the orchid can present these problems.
Sunburned leaves are not just due to direct sunlight either. If you moved your orchid to a bright-shaded environment but it was directly above a floor heater, then the hot draft of dry air can also burn the leaves.
Sunburned orchid leaves will turn brown, and this is due to high temperatures or direct rays. Verify that your orchid is in a place that it well-lit and in the right amount of sun. Some orchids detest bright light while others can’t bloom without it.
If you have a living room that doesn’t get a lot of light, then the orchids listed in this article
will help you buy orchids that will adapt better to your growing conditions. I wrote this article when I realized that my home didn’t have any decent windows.
I ended up buying a grow light because I just couldn’t live without Cattleyas. 😊 If you aren’t sure what are the light requirements for your orchids, this other article
I wrote might help you get a general idea of how to set up your orchids in the right amount of light.
4) Orchid Leaves Turn Brown Due to Salt Build-Up
Some orchids are more sensitive to fluctuations in the pH of the water, while others are more sensitive to the chemicals in the water. You need to get to know your orchid and read up on the specific care guides to know what pH is best and how water will influence this choice. A good place to start is in this guide
where I talk about the difference between hard and soft water. If you have a Paphiopedilum or any other orchid that is semi-terrestrial or terrestrial, the kind of water it will interact with will show up quickly in its browning leaves.
If you are using a pH that is too high, that lithophyte orchids prefer (orchids that attach to rocks) then your Paphiopedilum will present brown tips. Phragmipediums also have the same problem. The pH they prefer is a little lower than normal epiphyte orchids, around 4.5 to 5.5.
If your orchid is an epiphyte (grows on trees, for example, Phalaenopsis, Vanda, Cattleya, Dendrobiums, etc.) and you are using water that has a pH of around 5.5. to 6.5, then it’s probably that salt has built up in your potting medium, turning the tips of the orchid leaves brown.
The excess of sodium is as harmful to orchids as it is to humans. The salt build-up will show itself as a shinny sand-like glass particle that sparkles when sun hits them. They usually gather around the top of the potting medium.
Another common culprit of salt build-up is fertilizer. The excess fertilizer will quickly brown the tips of the orchid leaf, but it will turn yellow given a few days.
The yellow is intense and bright, and this leaf will die. The leaves most affected by overfertilizing will be the older ones.
Image Credit: © 2020 Orchideria. All Rights Reserved.
Don’t confuse the natural dying off of leaves with overfertilization. The excess fertilizer will brown and yellow your leaf in a matter of a week. The normal dying process could take months.
They can (and should) be washed out once a month with water that has no salt in it. This is s called flushing your orchid.
To know if this is what is happening to your orchid, the very tips and ends of your orchid will start to turn brown. They will turn crunchy and wilt. The middle of the leaf will still remain green and healthy, but the brown will slowly progress.
5) Orchid Leaves Turn Brown Due to Fertilizer Deficiency
If salt build-up was one reason, the other end of the spectrum, lack of nutrients, can also cause orchid leaves to turn brown.
This is the lack of two main elements: phosphorous and magnesium. The main way to know the difference is that this one will not kill the orchid leaf in a week like overfertilizing and salt build-up will.
This will take a month or two—slower, but still deadly.What happens in this method is that the lack of these two elements hinders the way the orchid would absorb and produce energy.
Let’s look at the first one: phosphorous.
Phosphorous is the famous energy building and storing element that is in ATP. Remember those ATP’s from science and chemistry class in high school? This is where they are important. The ATP (Adenosine Triphosphate) is broken down into ADP, Adenosine Diphosphate. See the phosphate in there? That is what is important in energy production and storage.
Without phosphate the plant lags along, flopping around lifelessly as it if had some sort of plant depression. There is not enough energy to keep the plant healthy and your orchid literally cannot summon the strength to grow.
This lack of Phosphate will also turn the orchid leaves a reddish-brown color.
In essence, it’s the green chlorophyll dying inside the leaf, but it can easily be reverted by fertilizing. It’s common to think that the reddish tones that look brown are in fact the natural sunscreen that the orchid produces, but it’s not.
The orchid does produce anthocyanin, a purple-freckled dotted spots that appear when the light is too bright but still bearable. The reddish-brown tones due to lack of phosphorus is a more uniform coloring and does not depend on lighting. The second element that could be lacking in your orchid that turns the leaf brown is Magnesium.
Rusty brown spots will appear scattered in the middle of the veins in the orchid. This happens because there is not enough energy to support the chlorophyll.
Magnesium is important, along with calcium, to maintain a healthy orchid leaf. These are not transported throughout the leaf and the spots occur.
To fix both these problems, you can use Epsom Salts or Cal Mag, a fertilizer that has these supplements in them. In this article,
I explain the use of Epsom Salts and how they are beneficial for your orchid. In this other article
I explain 5 unique ways to fertilize and go over the main elements in an orchid fertilizer
. If you think that under fertilizing might be the problem, that is a great place to start reading. You can also download the fertilization guide for free. The link is below.
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If this article has been useful so far and you want more information about orchid care, please subscribe to my newsletter. You'll get a 14-page fertilization guide to download as a gift.
6) Orchid Leaves Turn Brown Due to Inadequate Humidity
The last reason for orchid’s leaves to turn brown in the lack of relative humidity in the air.
Orchids do not do well in our home environments without a supplement of humidity. There aren’t enough water droplets in the air to actually help the orchid live and thrive.
Most orchids come from a tropical or subtropical environment where humidity is always above 50%. Without a humidifier, this is almost impossible to achieve inside our homes.
You can try the bathroom, but I don’t recommend keeping orchids there. In this article
I explain why bathrooms aren’t the best place for orchids. Kitchens aren’t that great either, even though all the design magazines have orchids in both these places.
The best place is where your orchid get enough light and humidity. We usually get the light right, but we err when it comes to humidity. Phalaenopsis, for example, like to have around 40% humidity. Our home environments, due to air conditioning and central heating units, will bring the relative humidity (rH) down to 27 to 33%. This lack of humidity makes the orchid leaf brown and crumble.
The first part of the orchid that will feel the lack of humidity is the aerial roots. The roots that project outside the pot will slowly become crunchy and wither. They will die off one by one. It’s hard to notice on a day to day scenario because this could talk a month or two to occur.
After the aerial roots die, then the orchid leaves will take the hit.
This browning will first start off but a loss of shininess to the leaf. Orchid leaves are usually very shinny (when clean) and have an adequate gas exchange. Without the adequate humidity levels, the orchid withers away and turns brown, limp and lifeless.
This point is almost exactly the same as the first point, the overwatering. It’s hard to tell which it is, and in fact, it can be both—a lack of water and a lack of humidity.
If you do not have a humidifier, I suggest buying one. This is the one I have (Affiliate Link),
but I’d prefer you to read through this article
of how I chose it. The one I bought might not be the right one for you and in that article, I explain the 4 types of humidifiers and how to pick the best one for your needs.
In summary, orchid leaves are a sure sign that your orchid is healthy or not. If you want to know 13 foolproof signs that your orchid is in fact healthy, this article
should be the next place you go. Orchid leaves are just one of those 13 signs.
Anywhere from overwatering, brown bacterial spot, severe sunburn, salt build-up, lack of elements in fertilization, or an overly dry home can turn your orchid leaves brown.
I've always found it hard to remember where I read something in the middle of an article, so to make it simpler for you, the articles mentioned or referenced during this tutorial are listed again below:
-Black Spots on My Orchid Leaf
-33 Low Light Orchids That Love Shade
-Light Requirements for Orchids
-What's the Best Water for Orchids?
Soft, Hard, Distilled and Reverse Osmosis Explained
-Epsom Salts for Orchids
-5 Unique Ways to Fertilize Orchids
-Best Humidifiers for Orchids
(Product Reviews)-13 Signs of a Healthy Orchid
If you have any questions, comments, or overall liked this article, please comment in the section below. It’s always great to interact with other orchid growers. I by no means am I an expert, but I love to share what I know so we can all learn as we go.