The Basics of Browning Avocado Tree Leaves – Why it Happens
Avocado is a popular and delectable fruit enjoyed by many. With its buttery and luscious texture, it is one of the most consumed fruits in the world. The demand for the fruit is increasing in recent times, driving the production of more varieties. However, a common problem many avocado tree owners have brought up recently is concerned with leaves turning brown. To understand why avocado tree leaves turn brown, we must first look into the basics of its ecology.
Avocado trees are deciduous, or evergreen trees, native to Central and South America. They can flourish in warm climates and withstand occasional frosts. Some of the benefits of growing avocado trees are that they are drought-tolerant, disease resistant and don’t require watering or fertilization. Avocado trees thrive in well-drained, rich soil. They can be used to beautify landscapes, as their glossy green leaves give a pleasing aesthetic effect.
Avocado tree leaves are desirable as they naturally stay a deep green color. However, when the leaves start to brown, especially on the edges, that’s a sign of distress. To understand why the browning of the leaves occurs, let’s further break it down.
Reasons for Browning Avocado Tree Leaves
Avocado trees require adequate amounts of water but cannot withstand flooding. Too much water can cause the leaves to brown and eventually wilt. Often this happens when the soil is clay-like, which means it doesn’t absorb water easily. Nutrient deficiencies can also cause the leaves of avocado trees to brown. It’s important to give the trees enough nutrients, through fertilizers and organic matter, particularly when the trees are circulating or fruitless.
In most cases, the reason avocado tree leaves turn brown is due to environmental factors, such as too little or too much water and lack of proper nutrition. This could be a result of the owner improperly caring for the tree. If the leaves are browning due to environmental stress, the problem can usually be reversed by adjusting the tree’s care regimen. If the leaves are browning due to disease or pests, then the owner must supplement appropriate treatments to the tree.
Brown discoloration on leaves can also depend on the time of year. Leaves, especially older ones, can start to brown when the tree is going into dormancy. This is naturally occurring and should not cause too much concern. Younger leaves will usually remain green. However, if more of the tree’s leaves than usual are browning, that is a sign of trouble and should be addressed.
Avocado Fungal and Bacterial Leaf Spot
Avocado Fungal and Bacterial Leaf Spot is one of the most common causes of browning leaves on avocado trees. It is caused by fungi and bacteria that live on the leaves and are activated when wet weather increases. As a result, the leaves become spotted, discolored and easily drop off. To protect the tree from further leaf spot problems, fungicides can be used. The tree should also be pruned to maximize airflow and reduce humidity and moisture.
Other weather-related diseases can also lead to browning leaves. An example of this is anthracnose, which is caused by a fungus and commonly shows up as wilted and brown leaves. To prevent the spread of anthracnose, the tree should be checked regularly and pruned when infected. Fungicides can also be applied.
Mites and Insects Infesting Avocado Trees
Mites and insects can also be a factor in why avocado tree leaves turn brown. Mites, in particular, are difficult to spot until their presence becomes overwhelming, as they are minuscule in size, but they can cause leaves to become brown and eventually shed. To get rid of mites, the tree should be sprayed with insecticides. It is best to spray the tree before the mite population becomes too high.
Insects such as borers, scale and mealybugs can also infest avocado trees and cause the leaves to brown and eventually drop off. In addition to spraying insecticides, another form of control for these insects is a physical removal. All of the affected leaves should be removed from the tree and properly discarded.
Excess Sun Exposure
It is important that avocado trees get the right amount of sunlight. Too much direct sunlight can cause the leaves to burn, resulting in brown spots. Too little sunlight can cause the leaves to lose their vibrant green color. It would be best if the avocado tree is planted in a location with partial sun, or receives at least six hours of sun per day with some shade.
In addition to too much or too little sun, avocado trees can also be adversely affected by windy conditions. Ensure that when planting avocado tree, it is in a location that is not exposed to high winds. When the wind is too strong, the leaves will often turn brown and the tree can become stressed.
Pests and Diseases Could be the Culprit
Insects and fungi are unwelcome guests for any avocado tree. If the tree isn’t receiving the proper care and treatment, it can become more susceptible to pests and diseases. If the tree has browning leaves, it is important to scan for pests or diseases and to assess the tree’s needs for proper nutrition and water.
Fungal leaf spot, in particular, is worrisome. This is when the spots start to appear on the leaves, darkening and broadening as they spread. In extreme cases, affected leaves will eventually drop off the tree. If this is the case, treat the tree with fungicides and prune and discard the affected leaves.
Insects can also cause browning leaves. Scales, mealybugs and borers can be hard to spot but they can quickly damage the tree if not taken care of. To address this issue, prune, spray with insecticides and keep the tree vigilant.
Nutrition for Optimal Health
Avocado trees need an adequate amount of nutrients to maintain their health and fend off diseases. However, too much fertilizer can also be a problem, as it can burn the leaves, causing brown spots. Therefore, it is important to regulate the amount of fertilizer used for the tree to adjust its needs accordingly.