Almond nuts are one of the world’s most famous nuts. They contain vitamins, minerals, protein and fiber, and so may offer a number of health benefits.
Almonds are one of the most consumed nuts in the country yet only a handful of these people know how to properly cultivate it.
In this article, we take a deep dive into the challenges faced by almond growers and some insightful solutions that can solve these problems.
Why Is My Almond Tree Losing Its Leaves?
An almond’s life cycle begins in late February after harvest from the last season. After losing their leaves each fall the almond tree spends the winter in a period of dormancy, storing up nutrients and energy for the coming growing season.
During this period, the farmer will conserve 4 or 5 healthy branches and prune the others so that sun can reach the budding leaves when springtime comes.
Leaf loss can also happen during the summer. If the pattern of falling leaves is well distributed throughout a tree and generally results in thinning of leaves, that tree is still considered healthy.
Trees can sometimes produce more leaves in the spring than they can support during the summer. Heat stress and other cultural factors like phytotoxicities will cause a tree to drop leaves it cannot support with the available soil moisture. Leaves that drop are often yellow with no discernable disease spots. A good way to maintain the tree’s health is to keep watering it during dry periods.
Why Are My Almond Tree Leaves Turning Brown?
A healthy tree can sometimes have brown leaves or dead branches. While this may seem natural, it could also indicate that you have a dying tree. Browning of leaves on your almond tree may be due to any one of the following:
Brown tips are usually a sign of salt build-up. Toxic levels. Exorbitant salt presence prevents water transportation which inadvertently causes new leaves and needles to die or turn brown.
Frost damage occurs when the intercellular fluid within plant cells freeze and form ice crystals. The crystals then rupture the cell wall, injuring the plant from the inside. Due to loss of turgor pressure, the leaves wilt down and eventually become crispy. While it is tempting to remove dead material from the plant, it is important to wait till temperatures are hotter to determine the extent of damage. This will prevent accidentally removing living tissue that survived the freeze.
Insects And Diseases
Pests and diseases negatively affect plants’ growth and reproduction. The prevalence of almond diseases heightens in extended periods of moisture and humidity. Shot hole, rust and Alternaria leaf spot are some of the common leaf diseases of almond trees.
Soil compaction occurs when soil particles are pressed together reducing the pore space between them. A heavily compacted soil has higher density and has a reduced rate of drainage. Almonds are deep-rooted plants hence their roots have to exert more strength to penetrate the soil.
Consequently, water infiltration and gaseous exchange between the plant and the soil becomes difficult. The lack of nutrients, water and gasses diminish the growth of the plant and may lead to wilting and ultimately browning of its foliage.
Plants need water in moderate amounts to aid the growth process. When plants don’t get enough water, the pressure inside the stems and leaves drop and they wilt. If the soil around a plant is dry, it may need more water.
Excessive Exposure To The Sun
Brown leaves are often related to over exposure to the sun, a condition referred to as leaf scorch.
Too much loss of water through the leaves by the sun will cause leaves to turn brown and scorch. In extreme cases, sun scorch causes plants to lose their leaves. This leaves the plant weak and susceptible to diseases.
Why Are My Almond Leaves Turning Yellow?
Chlorosis is a condition in which leaves produce insufficient chlorophyll. Possible causes of chlorosis include poor drainage, compacted roots, high alkalinity and nutrient deficiencies in the plant. Iron and manganese are needed by plants to form chlorophyll necessary for photosynthesis. Deficiency of these nutrients can cause chlorosis.
Most of the time, if your plant’s leaves turn yellow, it’s a sign that you’re either under watering or overwatering it. Plants need water to survive, and if they’re not getting enough of it, they’ll drop leaves in order to conserve their supply. Chlorosis in some almond trees can be linked to irrigation techniques in the orchard.
When a group of almond trees located in the same area exhibit similar patterns of chlorosis, it is likely that the sprinkling system watering them is faulty. Either they are getting twice as much water as other trees or just a quarter of it.
Damaged roots can also cause leaves to turn yellow. The yellowing appears during hot weather and the compromised roots are unable to keep up with the water needs of the tree.
Why Is My Almond Tree Not Producing Almonds?
An almond tree not producing nuts is a failure on a commercial level and it can be a letdown for the local farmer. One of the reasons why you are not seeing any nuts might be that you just haven’t waited long enough! As perennial plants almond trees start bearing fruits in the third year after planting and do not yield maximum output until the seventh year.
Another issue may be pollination. Every almond you eat exists because a bee pollinated an almond tree blossom somewhere. Most almond trees are self-sterile and require cross pollination from trees blossoming at the same time. If you don’t have the right combination of the different species, you can’t get nuts.
The pollen is heavy and sticky and needs insects to transfer the pollen. For the most part, wind pollination is not effective so commercial growers use honey bee colonies for this purpose. Self-fertile varieties require fewer bees per acre to achieve good pollination rates. Once an almond tree begins fruiting, it will do so for the next 25 years. 1
Why Is My Almond Tree Not Flowering?
Almond trees are known to be self-incompatible which means that it is unable to be fertilized by its own pollen. For a successful pollination, a pollinator (such as the honey bee) needs to transfer pollen between two trees of different varieties that happen to be blossoming at the same time.
Almond trees typically bloom in February and March. During this time, bees flit from tree to tree, pollinating almond blossoms along the way. Honeybees are the most economically valuable pollinators of crops worldwide. A 2007 study showed that 35% of the world’s food crops depend on animal pollinators of various kinds. Other insects that help in pollination of almond trees include blue orchard bees and wild bees.
Another reason why you haven’t seen flowers on your almond trees could be improper pruning. Almonds are normally pruned after blooming when new buds have not yet started growing. Pruning almond trees in early spring or during fall may result in removal of flower buds that have already formed. Repeated years of pruning in almonds have been shown to reduce crop yields.
Almonds require a large amount of water to survive. If the tree isn’t receiving enough water, it may divert its energy and resources to searching for water at the cost of flower production.
It is also possible that your almond tree isn’t flowering because of an underlying disease. Brown rot blossom and twig blight are both fungal diseases that affect almond trees. They cause the blooms to wither and drop and ultimately nut yield.
Why Is My Almond Tree Dying?
As living things, plants require nutrients, air and water to grow. When these vital resources are withheld from them they tend to starve and die. The average almond tree has a life expectancy of 20 to 25 years. However certain factors can cause the tree to die prematurely.
There are many reasons for sudden tree death in almonds including root damage, microscopic pathogens, over fertilization, drought and so on. Very often, almond tree death is related to moisture issues. Almonds are thirsty permanent crops that require water all year round. When there is too little water, the trees will wilt and wither away. Insufficient water can be caused by bacteria too.
Xylella fastidiosa is a bacterial disease of plants caused by an organism (Xylella) that lives in the xylem of plants. When xylem vessels are plugged or blocked, then it might result in loss of availability of water in surrounding receiver cells; which ultimately reduces the turgor pressure. This will lead to loss of rigidity of cells and lead to wilting.
A dying tree has an abundance of dead wood and its bark is brittle. It may suddenly develop a lean figure and may show signs of root damage. If you see these signs on your almond tree you should contact your arborist as it gives you a better chance of saving it.
How Do I Protect My Almond Trees?
Like all living things, plants require optimum conditions of temperature and environment to thrive in its ecosystem. Almond trees grow best in etesian climates. In other words, they do well in areas that have long summers with dry, hot, and sunny weather. Such areas may have small, mild, and wet winters.
Almonds require at least 6 hours of sun per day to ensure full blooming. The optimal temperature for growth is between 15 – 30 °C. Almonds thrive in well drained loamy soil. They require a planting depth of about 6 feet.
This is done by creating mounds around the planting site. It is important to till the soil so as to loosen it up and prevent soil compaction. While pH is normally not a limiting factor, almond trees will thrive well in soil pH around 6.5 to 8.
Fertilization can be done once or twice a year, usually in spring. A balanced ration of NPK fertilizer is applied at a 3-foot radius from the tree to provide nutrients that can be taken up by its roots. Maintenance pruning is done to remove dead branches and preserve the shape of the tree. Keep in mind that if cover crops are planted in the almond orchard, you may have to increase water supply by almost half, especially during early spring.
What Diseases Can Almond Trees Get?
Despite the almond tree being a hard and sturdy one, there are a number of diseases and conditions that can terminate its life. These diseases are caused by various kinds of pathogens and can be spread transmitted by pests and insects.
The most common diseases that afflict almonds are caused by fungi and they include anthracnose, brown rot, Ceratocystis canker, leaf blight and hull rot. Others include bacterial diseases like Almond leaf scorch and crown gall, viral diseases like peach mosaic and calico, and noninfectious bud failure which has a genetic cause.
Many of these diseases can be prevented by practicing good sanitation and ensuring that affected branches are pruned to reduce the incidence of spreading. 2
What Causes Almond Diseases?
From severe weather to insect infestation and transplant shock, there are a number of factors that can cause problems for almond trees. In most cases, insects and pests are either directly responsible for the disease or they act as hosts that transmit the pathogens causing these diseases. Some common almond pests include fire ants, spider mites, leaf-rollers, tree borers and forest-tent caterpillars.
Chemical treatments are available for trees with minor infestations, however this is a specific remedy and may not work in all cases.
Citations Used In This Article
- Almond Tree Not Producing Nuts: Causes For An Almond Tree With No Nuts (gardeningknowhow.com)
- List of almond diseases (Wikipedia).