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Why Is My Avocado Tree Leaves Turning Brown?

Publish Data: May 21, 2021

by Abid Hasan Khan

Are you worried about your avocado leaves turning brown? Just a few years ago, I faced the same problem when I started to grow avocado trees in my garden. But over the years, I have learned enough practical knowledge to provide you with an elaborate answer. So, I hope that after reading this article, you will find a suitable solution to your problem.

The prominent reason for leaf browning is excessive salt accumulation. That happens due to excess chloride in your irrigation water. In addition, anthracnose disease, root rot, mineral deficiency, inadequate irrigation, etc. can turn avocado leaves brown gradually.

To prevent all these issues, you need to leach out your avocado trees. Approach any of the two leaching methods mentioned below. In addition, check your soil and irrigation water carefully to prevent any harmful pathogen from harming your trees. Continue reading the rest of the article to get detailed information about this.

dyeing avocado tree leaves turning brown FI
Shamus O’Leary / YouTube

Five Reasons for Avocado Leaves to Turn Brown

You will find five significant reasons other than bright sunshine responsible for your avocado leaves to turn brown. Read about these five issues carefully and find out which one matches the condition of your trees.

1. Excess Accumulation of Salt

If you live in a region near to a sea or a river that is the source of salty water, there is a chance that your irrigation water for avocado trees will have excess chloride in it. For Southern California of the United States, you will find that most of their water comes from the Colorado River. This may create an issue of salt accumulation.

If you don’t notice in time, this will result in significant damage to your trees. As symptoms, it will appear as burned leaf tips causing an early fruit and leaf drop due to salt accumulation at leaf edges. In addition to your irrigation, shallow watering, improper fertilizer application, soil moisture deficiency, etc. may cause salt accumulation in your avocado leaves.

To put an end to this issue, you need to leach out the excess salt from the root. In this case, you can try watering your trees as close to the soil surface as possible. Most people repeat this process after every 3 or 4 weeks.

2. Inadequate Irrigation

It is very crucial for you to remember that your avocado trees can get brown-tipped leaves during the fall season if they receive inadequate soil moisture. Your tree can only take a certain amount of chloride, any overconsumption or less consumption is both bad for its health. This can also happen if the area you live in gets less rainfall. To prevent this issue, always make sure that the water you use for irrigation has enough nutrients especially minerals. So, check carefully for brown leaves and keep track of your irrigation daily.

3. Anthracnose Disease of Avocado

Notice if your avocado trees have leaves that have turned yellowish. If you don’t check daily, the leaves may get tip burn and later turn brown. This disease in particular is known as avocado anthracnose. It is caused by the fungus known as Colletotrichum gloeosporioides.

If you continue splashing water to the canopy after this, the fungal spores will spread more. As a result, it will cause infection to the fruits and twigs too. You may even notice lesions on the shoots and fruits, fruit drop, fruit decay, etc. which will ruin your trees’ overall health.

To prevent this problem, you need to perform pruning once in a while to remove any damaged part of the tree. Try not to prune in cold weather, this may lead to stunting and slow down the growth process. To know more about the pruning process, read the article titled “How to prune an avocado tree on our website.

4. Deficiency of Iron

Check properly if your soils are alkaline or not. If you are not sure about this, consult a soil specialist or take a sample of your soil to the local garden center. If there is alkaline soil near your trees, it may result in iron deficiency. You will notice the symptoms like tip burn, yellowing of veins, leaf drop, etc. Make sure your soil is not too alkaline. Never encourage poor soil drainage at the base of your trees, it may also result in iron deficiency.

5. Root Rot due to Pathogen Attack

Notice the canopy of your trees carefully. If you find your leaves to be pale, wilted, and have brown tips, there is a chance that your trees are suffering from avocado root rot. In general, it is caused by the Phytophthora cinnamomi algae. It is a soil-borne water mold and one of the worst plant pathogens.

If your avocado trees are affected by this pathogen, they will face slow growth, resulting in smaller canopy and fruits. It may also have significantly smaller roots that are unable to provide enough nutrition to the upper portion of the tree. As a preventive measure, apply enough fungicide to your trees so that the growth of pathogens does not continue near the roots. Make sure you plant those trees on a well-drained site. In addition, take care so that the soil at the base of the tree is not soggy.

Why Does Browning Occur on Indoor Avocado Leaves?

Even after you work so hard on your indoor avocado plants, sometimes the avocado leaves will turn brown due to dry air which has fewer water molecules. During the summer season, your indoor humidity usually falls. And if that air becomes very dry, evapotranspiration occurs i.e. the leaf cells start to lose water more and more. The small and thin leaves of your plants tend to lose more water particles as a result. Slowly, their cells start to die and that initiates leaf browning.

To put an end to this problem, you must increase the humidity near your trees if you feel the air is too dry. If you love your plants so much, then you should buy a humidifier as soon as possible. Using that, try to keep the humidity level in the range of 45% to 55% nearby your plants. This will keep your young leaves enriched with water molecules. Therefore, your plants will stay healthier, and the leaves will stay greener in all seasons, summer, winter, and spring.

Leach Out your Avocado Trees to Prevent Browning

You will find two widely known methods for leaching. One is to use micro-sprinklers and the other one is to add “leaching fraction”. Most farmers apply the first method for better results. But if you ask your fellow gardeners, most of them will talk about the second method if they do not have micro-sprinklers in their garden.

If you have micro-sprinklers available in your garden, use them to run water to the base of the trees for up to 24 hours. Continue to do this once a month for July, August, and September. If your trees are older and more mature, then this method of leaching will be more suitable than the second one.

The other method that you can apply is the addition of “leaching fraction” to your trees. Here, you do not have to use any micro-sprinklers or run continuous water for 24 hours. All you need to do is add a little extra water portion each time you irrigate. But note that this extra portion should be no more than 20 percent of the regular irrigation. You will find this method very useful if your trees are younger.

Final words

Avocado leaves show a variety of symptoms to certain diseases and changes, as it is one of the most sensitive gardening fruit plants. As a good gardener, it is your responsibility to check your plant condition daily to know about its overall health. If you manage to spot leaf browning earlier, you will be able to treat this condition before your plants die or develop fungal diseases. So, irrigate your trees with enough nutrients and take preventive measures before anything goes wrong. Consult a soil specialist and keep in touch with your fellow gardeners for more experience.