Why Do Coffee Plant Leaves Turn Brown? Discovering the Main Reasons

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Have you ever wondered why your coffee plant leaves turn brown? Well, there are several causes for this occurrence. Keep reading to learn more.

A coffee tree, known as Coffea arabica, is a bush that grows solely in the U.S. is the primary source for coffee extraction. Hence, the U.S. Department of Agriculture plants the hardiness zones. 

This evergreen shrub, which can grow up to 15 feet in height, produces vivid red berries, nestling the coffee beans inside. Those are the same ones we later roast and steep in our caffeinated beverages. However, the coffee plant leaves tend to turn brown and fall off after a while. 

There are many reasons why that happens. These reasons include a common disease or inadequate environmental conditions such as low humidity or scorch. Keep reading to learn why coffee plant leaves turn brown and how you can prevent it.

Why Do Coffee Plant Leaves Turn Brown?

Coffee plants thrive in pots and, to many people’s surprise, can grow indoors as well. If you want to cultivate the tree in the hopes of reaping some coffee beans, you should pick the Arabica coffee variety to plant.

When it comes to the environment in which they grow, coffee plants are finicky. If the humidity in the air is too low for their liking, they most likely turn brown. Too much sun is also a no. Such exposure can result in them turning brownish, thus losing their sheen and aroma. Aside from that, coffee leaves may become yellowish-brown due to some fungal infections.

How to Detect Brown Leaves of Your Coffee Plant? 

Whenever your coffee plant detects sub-bar conditions, the leaves will begin to darken and adopt a different tint. Their usually luscious green color becomes mossy or even seaweed green as the situation progresses. Generally, you can spot this on the edges of the leaves. All changes originate from that area. Often, you’ll notice them coiling and drooping, and that is a cause for alert. When not sure, feel free to examine the texture without wearing gloves. If the leaves are dry to the touch, it means the change has already begun.

So, be warned about such subtle but quite relevant signs. Many shun them aside, figuring it’s a passing malady, yet, it might be already too late. However, if you are quick to take action, you might just make it in time. In short: it’s not an irreversible process. 

Main Reasons Why Coffee Plant Leaves Turn Brown

You won’t be able to treat your plant adequately if you don’t identify the root cause of the problem. Hence, these are the most typical causes of coffee leaves turning brown.

1.     Low Humidity Levels

The coffee plant does not require a high humidity level. However, always remember that  Coffea arabica is a delicate plant. As such, it relies heavily on proper humidity levels. For optimal growth, you must keep the relative humidity above 50 percent. In turn, this allows the plant to resume its necessary functions, like evapotranspiration. It is a technique through which coffee plants and other houseplants release humidity into the vital air.

In a similar vein, evapotranspiration allows your coffee plant to acquire all the essential nutrients from the soil. Magnesium and potassium are two minerals that contribute to the strength of the coffee leaves. Low humidity, which hinders evapotranspiration, may prevent leaves from obtaining these nutrients. In time, this deficit may result in their deterioration.  

2.     You’re Not Watering Your Plant Appropriately 

So, your coffee plant may thrive at a specific humidity level. However, if you do not maintain a regular watering schedule, that alone will not be effective. What happens to your plant’s transpiration when it does not get enough water?

Once your coffee plant is supplied with nutrients, water is responsible for their efficient distribution. If the liquid is in short supply, some parts of the plant will not get their turn. Often, the leaves come last in line since they are the farthest ones from the roots. Next, you’ll notice them shrinking or curling. This is a common sign of a lack of nutrients.

3.     Scorch From Direct Sunlight Exposure

Coffee plants are often short and found in the understory of forests. They reserve those locations to flourish under larger trees’ shade. Hence, they are stingy in how much sunlight they prefer. In short, coffee plants are not fans of basking in the sun. So, because of that natural habitat, too much heat can damage them. Also, this sensitivity to higher temperatures is connected to their “diet”. Coffee plants rely on protein enzymes for most of the “actions” they perform. 

As a consequence, direct sunlight might inhibit their development. It is possible that the plant’s stem may disintegrate before blossoming. Visually, those green leaves will darken and begin to decompose. Next, brownish spots will appear on their skin. At that point, they can easily fall off with a single touch.

4.     Fungus Are Consuming Your Plant

Fungal infections are the primary cause of concern when cultivating coffee plants. If they take hold, these organisms will ruin your efforts. The contamination will soon manifest as the distinctive “coffee leaf rust.” Hemileia vastatrix is the culprit responsible for the majority of coffee plant illnesses.

Fortunately, you can detect fungal issues in your coffee leaves before they become dark brown. This is because they undergo a progressive color shift as the fungus spreads. Plus, during the transition from green to brown, the leaves exhibit orange and rusty tinges.

Wrapping Up: Taking Care of Your Coffee Plant

By creating an environment that mimics the natural habitat of your coffee arabica plant, you ensure its longevity and fruitfulness. This plant thrives in low-sunlight and high-humidity conditions. Hence, to prevent your plant leaves from turning brown, add a humidifier and often water the plant. Once a month, or as soon as it blossoms, remember to treat it with a fungicide.

If you keep up with this method, the risk of the leaves going brown will continue to dwindle. As a result, you’ll enjoy a bountiful season.

Like this article? You might want to read: What Is Organic Coffee And How Is It Different From Inorganic