Do you have a palm tree in your backyard? Have you noticed its leaves turning yellow? If so, you may be wondering what’s causing this change. Not to worry – we’ll explain why this happens and how to keep your palm tree looking healthy and green. Read on for more information!
What Causes Palm Tree Leaves to Turn Yellow and How to Fix It
Palm trees are incredibly hardy plants once established and when properly cared for, but there are a surprising number of reasons why your palm tree’s leaves may turn yellow.
The most common reasons are related to improper watering – meaning you’re either giving your tree too much water or too little water. The symptoms of these can mimic each other, so it can sometimes be hard to tell which it is.
We’ll discuss each in detail further down the article to help you determine whether this is the reason your palm’s leaves are turning yellow.
If your palm tree’s leaves are only turning yellow in places, it may be that your palm tree has a nutrient deficiency and needs to be fertilized. How the yellowing manifests (e.g. oldest leaves turning entirely yellow, leaves developing yellow spots, etc) will let you know which nutrient your palm tree isn’t getting enough of.
For indoor plants, the most common reasons after water and nutrients would be related to insufficient light and low humidity. These can both cause yellowing of leaves, while light may cause some leaf drop and low humidity would cause brown leaf tips.
Before I go further into detail on each, here is an overview of most of the reasons why your palm tree’s leaves may be turning yellow:
- Improper Watering: When your plants are overwatered, the performance and vigor decrease, which can lead to yellow leaves on your palm tree.
- Insufficient Light Conditions: Palms need plenty of light to stay healthy, so if your tree is not getting enough light, its leaves may start to yellow.
- Nutrient Deficiency: If the soil your palm tree is growing in lacks essential nutrients, it can cause the leaves to yellow.
- Pests: Damage from certain insects can cause yellowing in some cases.
- Low Humidity: Low humidity can also cause yellowing of palm leaves.
- Fungal Infection: Fungal infections can cause brown or yellow leaves on your palms.
- Bacterial Infection: Bacterial infections can be extremely dangerous to palm trees, starting off with yellowing leaves and leading to palm death in some cases.
- Viral Infection: In addition to fungal and bacterial infections, there are some viral infections that can cause yellowing leaves in palm trees, in addition to other symptoms.
- Iron Deficiency: Palms with a damaged or inadequate root system may suffer from iron deficiency, which can lead to yellowing leaves.
- Soil PH: If your soil’s PH is outside of the ideal range for your species of palm tree, it can prevent uptake of nutrients from the soil and cause yellowing that mimics the signs of nutrient deficiencies.
Identifying and Resolving Nutrient Deficiencies Causing Yellow Leaves in Palms
Nutrients are essential in keeping your palm tree healthy and vibrant. When a deficiency of essential nutrients is present, the palm’s leaves will start to turn yellow. It is important to identify the nutrient deficiency and take steps to resolve it.
When identifying whether the palm tree has a nutrient deficiency, it is important to look at the pattern of yellowing of the leaves. If the yellowing is confined to a single side of the frond, is located at the base of the frond, occurs only in spots, or occurs on the outside of the fronds while leaving the centers green, then it is likely caused by a nutrient deficiency.
It is also possible to identify the nutrient deficiency by looking at the pattern of the yellowing on the leaves more closely.
Identifying the Deficiency
Magnesium Deficiency:
If the leaves are mainly yellow but with green tips or veins, this is likely due to a magnesium deficiency. Magnesium helps the tree transport nutrients and aids in photosynthesis, so a lack of magnesium can cause yellowing of the leaves.
Iron:
If the leaves have yellow edges with green veins as well as brown tips, this could be due to an iron deficiency. Iron helps the tree absorb nitrogen, so a lack of iron can cause the leaves to become yellow or brown.
Other symptoms of an iron deficiency include yellowing or bronzing of the leaves, stunted growth, and a decrease in overall health of the tree. The most common symptom is yellowing of the leaves, particularly in the younger fronds. The yellowing or bronzing of the leaves starts at the edges of the leaves and spreads to the center. Leaves may also become brittle and curl downward.
Stunted growth may also occur, making the tree appear shorter than it should be. Additionally, the tree may be less resistant to pests and diseases due to the lack of nutrients. Iron deficiency can be treated with foliar applications of iron chelate, but be sure to test soil before and after application to ensure an appropriate amount of iron is present.
Nitrogen:
Nitrogen deficiencies may cause the leaves to become a light green or yellowish color, but they are much less common due to the lower overall requirement for nitrogen in palm trees. This is most common when growing palm trees as houseplants.
Potassium:
Potassium deficiency in palm trees can cause older palm leaves to drop prematurely and cause the canopy to contain only a few leaves, all of which will be chlorotic, frizzled and stunted. The trunk may begin to taper (pencil-pointing) and death of the palm often follows.
Symptoms of potassium deficiency may vary among species, but always appear first on the oldest leaves, such as orange and yellow spots or marginal necrosis symptoms.
Once the nutrient deficiency has been identified, the next step is to determine what to do about it. The best way to address the issue is to use a fertilizer specifically designed for palms. A slow-release fertilizer is ideal for palms as it provides the plant with a steady supply of nutrients. It is also important to ensure that the soil is moist but not soggy as this can cause root rot. Additionally, it is important to check the soil pH as this can also affect nutrient uptake. If the soil pH is out of balance, then the nutrients may not be available to the palm tree.
What To Do When You See Yellow Spots or Brown Tips On Palm Tree Leaves
Palm trees are susceptible to a variety of diseases, many of which manifest as yellow spots on the leaves. The primary cause of yellow spots on palm tree leaves is nutritional deficiency, specifically iron, manganese, zinc, and magnesium. Chlorosis can result when the tree is not able to access sufficient levels of these essential micronutrients.
When this happens, you should bring a few palm fronds showing the symptoms to your local extension center to get an idea of what nutrients your tree is deficient in so you can properly fertilize your tree.
Additionally, plant pests such as scale and mites can cause yellow spots on leaves. If left unchecked, the pests can cause serious damage to the tree. Diseases like Fusarium can also cause yellow spots on the leaves – typically when major sections of the palm fronds turn yellow and/or brown. These fungi can cause discoloration and decay of the trunk, which can eventually result in the death of the tree.
If your palm tree has fusarium wilt, there is no cure and the palm tree will need to be removed. Again, check with your local extension office to get a definitive diagnosis if you think your tree might have fusarium wilt.
Soil pH Imbalance
If the soil pH is off balance, it can cause the palm tree leaves to turn yellow. The pH of the soil is an important factor in the health of the palm tree, as it affects the availability of minerals and nutrients to the tree. A soil pH imbalance can be caused by either too much acid or too much alkaline in the soil. If the pH level is too low, then the tree is not able to absorb the nutrients from the soil. On the other hand, if the pH level is too high, then it can cause toxicity to the tree. To determine the pH level of the soil, you can use a pH test kit, which can be purchased at most garden centers. If the pH level is off balance, you can correct it by adding sulfur or lime. Additionally, you can also add organic matter to improve the soil structure and help balance the pH level.
Having the wrong soil pH balance can be a major contributor to yellow leaves in palm trees. The ideal pH range for most palms is 6.0 to 7.5. Depending on your individual palm species, if your soil pH is outside of this range, it can cause nutrient deficiencies and lead to yellow leaves. Some palms have a different range, however, such as the acai palm which likes 4.5-6.5.
To fix soil pH imbalance, you can apply a soil amendment to increase or decrease the pH level. If you’re unsure about the pH of your soil, you can get a soil test kit to test it. The soil test will tell you what amendments to use in order to bring the pH back into the ideal range for palm trees – namely dolomite to raise the PH or sulfur to lower it. Once you’ve adjusted the pH, your palm tree should be able to absorb the necessary nutrients and start returning to a healthy state, though it can take months for PH altering amendments to actually start working.
Drought Stress
Drought stress can also cause your palm tree’s leaves to turn yellow or brown and eventually fall off. When a palm tree does not receive enough water, it will start to show signs of dehydration, such as yellowing of the leaves. Drought stress can be caused by a variety of things, including lack of rain, inadequate irrigation, and improper soil drainage.
If you are seeing yellowing leaves due to drought stress, the best solution is to increase the amount of water that your palm tree is receiving. Make sure to water your palm tree deeply and regularly, and check the soil to make sure it is draining properly. In addition, mulch can help retain moisture in the soil and protect the roots from extreme temperatures.
Overwatering
Overwatering is one of the most common reasons for why palm tree leaves turn yellow. Palms need a lot of water, but they also need well-draining soil. If the soil is oversaturated, it can lead to root rot and yellowing of the leaves. In addition to yellowing leaves, you may also notice the stem turning brown and mushy at the bottom, the soil being consistently wet, and (if you dig a little) the roots will be brown or black (and perhaps slimy) instead of their typical healthy color.
To prevent overwatering, make sure to check the soil regularly to ensure it is not too wet. If the soil is too wet, reduce the amount of water you give the palm tree and aerate the soil to improve drainage and prevent root rot.
Fungal Diseases
Fungal diseases can be a major cause of yellowing in palm tree leaves. Fungi reproduce by releasing spores that can spread from plant to plant, leading to infection. Fungal diseases can be caused by poor air circulation, humid conditions, and wet weather. Symptoms of fungal disease include yellow spots on leaves, brown spots on leaves, and white or gray spots on leaves.
In severe cases, the entire leaf may turn yellow and die. To prevent and treat fungal diseases, it is important to keep the area around your palm tree clean and free of debris. Remove dead leaves and prune affected branches. Make sure to water your palm tree at the base, rather than from the top. Use fungicides to treat any existing infections and keep the area around your palm tree free of pests.
Bacterial Diseases
Bacterial diseases can also be a cause for yellowing palm tree leaves. Bacterial diseases can cause yellow spots, lesions, or streaks on the leaves. These spots will often have a yellow halo around them, and the foliage may turn yellow or brown.
Bacterial diseases can spread rapidly, so it’s important to address the issue as soon as possible. To do this, you should prune away infected leaves and spray the tree with an appropriate fungicide or bactericide. It’s also important to make sure the tree is getting enough water and nutrients, as these can help prevent bacterial diseases.
Some bacterial diseases, such as fusarium wilt can’t be cured, and the best solution is to cut the affected palm tree down and remove it completely. Also remember to disinfect any tools used to care for or remove the tree so they don’t spread the disease to other plants in your yard.
Insect Infestations
Insect infestations can also be a cause of yellowing in palm tree leaves. These pests can feed on the sap of the leaves and cause discoloration and possible wilting of the leaves. Some of the most common insects that can cause this type of damage include scale insects, mealybugs, aphids, mites, and thrips.
It’s important to inspect your palm tree leaves for signs of these pests, as well as for any damage caused by them. If you do find pests, you’ll need to take steps to get rid of them. This may include insecticides or other methods such as manually removing the pests with a cotton swab. Additionally, you may need to take steps to prevent future infestations, such as using a horticultural oil or neem oil spray.
Viruses and Nematodes
Viruses and nematodes are also a potential cause of yellow leaves in palm trees. These organisms are microscopic, making them difficult to detect. Symptoms of viral infections include yellowing and discoloration of the leaves, and stunted growth. Nematodes, on the other hand, can cause yellowing and wilting of the leaves. If you suspect that your palm tree has been infected with a virus or nematode, contact a professional for assistance. Managing these pests can be difficult and requires specialized knowledge.