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6 Common Orange Tree Diseases You Need to Look Out For

Orange Tree Diseases

Orange trees can be heavily affected by insects, fungus, bacteria and virus diseases. Discover the most common orange tree diseases to protect your trees.

If you have orange trees, you want to keep them at their healthiest, so they can provide delicious oranges for you for years to come.

So it's important you know about the potential orange tree diseases that can ravage orange trees. Because the more you educate yourself on what dangers are out there for your trees, the better you can be at preventing them from damage.

That's why we put together this post on six common orange tree diseases you need to be aware of.

That way you'll be able to understand the potential attackers of your orange trees!

Sound interesting? Keep reading to find out more.

Bark and Trunk Diseases

There are several dangerous bark and trunk diseases that you should be aware of with your orange trees. Unfortunately, some of them have no knowable treatment. 

Psorosis bark scaling virus disease is one such disease. It's often found often in older trees. It shows itself through peeling bark on the orange tree's trunk and branches. 

If your tree gets it, you should continue to care for the tree as normal, but if it gets girdled, you'll need to remove it from the soil when it dies.

Foot rot fungus is another disease without any known treatment. If you notice cankers and lesions around the base of the orange tree, it might be Foot Rot Fungus. This is especially true if those lesions have sap coming out of them.

While there's no treatment, you can take steps to minimize the chances of Foot Rot Fungus. For starters, plant your orange trees in well-draining soil, and with raised beds, if you have heavy clay soil.

Then make sure not to overwater them. That will make your chances of having a successful citrus season all the better!

Leaves Diseases

Sooty mold is a common disease of the leaves of orange trees. If you notice your leaves have blackened spots, it might be sooty mold. And while technically it's not a disease, but a fungus, it's still not great for your orange tree.

You can use a soap and water solution to wash the spots off. This will also help drive off the aphids and leafhoppers that leave the fungus in the first place.

Citrus greening is a bacterial disease that comes courtesy of the Asian citrus psyllid. The primary symptom is yellow mottling on the orange tree's leaves. Another noticeable characteristic is the midvein appears more pronounced than usual.

Unfortunately, there's no cure for this disease. But giving the tree proper general care will go a long way towards having it survive citrus greening.

Fruit Diseases

Citrus stubborn disease affects the oranges on the tree, causing them to look lopsided. This is because the seed pocket is pushed to one side. It's spread by leafhoppers and should be sorted by spraying the tree with insecticidal soap or oil.

Alternaria black fungus is another disease that has no known cure. It causes a black fungus to appear inside the oranges. It tends to be more common after rainy weather. You'll need to throw out any affected fruit and leaf litter.

Orange Tree Diseases

As you can see, some orange tree diseases are treatable, while others are not. But either way, proper care of your orange trees will help them survive and thrive. 

Check out our citrus tree collection to start growing your own citrus fruit or oranges!

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Under Attack? 5 Common Citrus Pests and How to Stop Them

Common Citrus Pests and How to Stop Them

Is your citrus tree under constant attack from insects or disease? Find out what citrus pests to look out for and how to stop them to protect your citrus trees.

Growing and tending to citrus trees isn’t always easy, especially outdoors. You’re constantly battling against Mother Nature and a seemingly endless number of citrus pests and fruit tree diseases bent on eating and destroying your fruits. If you’re able to fend off the onslaught of insects and drought days, then you’re rewarded with the fruits of your labor… literally.

Knowing is half the battle and being able to spot the telltale signs of these pests is the first step to defeating them. We’ve chosen some of the worst offenders with the goal of arming you with knowledge. Your citrus trees will be full of life and bearing delicious fruit in no time.

Grasshoppers Are Painful Citrus Pests

There are few more well-known heralds of spring than the grasshopper. Heading out into the yard and seeing these massive insects hopping from place to place is sure to bring a smile to your face unless they're chomping down on your citrus trees.

Grasshoppers start by chewing the leaf edges and move inward until only the primary vein is left. A few can be an annoyance, but grasshoppers can be prevalent by the thousands. They can strip entire small trees bare and have been the bane of many farmers.

Caterpillars are Not Just Butterflies

Caterpillars are even more beautiful than grasshoppers and they turn into moths and butterflies. What can be better than that? Many species of caterpillars eat citrus trees. They eat the leaves and shoots of young trees. The leaves can also be rolled and webbed.

The transformation into a butterfly may be attractive, but the damage done in preparation can be a nightmare for citrus growers. They feed on the leaves before entering their cocoon or web.

Citrus Leafminer Digs Into Leaves

The citrus leafminer isn’t looking for gold in the leaves like traditional miners and that’s bad news for citrus growers.

Just like miners, they dig tunnels under the surface of leaves that are either pale or black. Black tunnels are filled with excrement. You’ll notice the tunnels and leaves can be galled, rolled or distorted.

Citrus Whitefly Attracts Other Insects

Many citrus insects are easily spotted because they leave their marks on top of the leaves or chew the entire leaf. The citrus whitefly is sneakier and only eats the bottom of the leaves. They also lay their eggs and the larvae suck the sap from the leaves.

They excrete a substance called honeydew, unmetabolized sugar from the sap that sticks to the leaves and attracts other insects such as ants.

If you want to know if you’ve got a citrus whitefly infestation, just shake a few branches. The small white insects will detach and flutter around the tree.

Citrus Thrips Attack Leaves and Fruit

These yellow or orange insects do more than just damage leaves, they also attack young fruit. They want the tree sap and also lay their eggs. The larvae eat the leaves and fruit, especially during periods of hot weather with little moisture.

You’ll notice a citrus thrip infestation if you see silvery or scabbed fruit and silver-grey leaves that are curled or distorted.

Bounce Back From Tree Pests

These are only a few of the many citrus pests that can plague an orchard. Small young citrus fruit trees are the most vulnerable and those stressed by drought or disease. Learn the signs of these pests and protect your trees from citrus tree diseases.

For more information about citrus trees or their natural enemies, check our insightful video and instructions on citrus pest and disease control, and please explore our citrus blog.

Citrus Tree Diseases: 4 Common Ailments and How to Treat Them

Citrus Tree Diseases

Think something is wrong with your citrus tree? Read on to find out the most common citrus tree diseases and how to effectively treat them.

Many types of citrus trees can provide delicious fruit over their lifespans. However, like all plants, they are not immune to diseases and pest damage. Knowing the warning signs of common citrus tree diseases and pest problems can help you treat them before they harm or kill your trees. 

Citrus Tree Diseases: Citrus Canker

Citrus canker is a disease that, as its name suggests, can affect your citrus trees. The name comes from the yellow scabs that grow on the affected branches. Transmission can happen through the air, through animals, or through insects, and can spread rapidly.

If you see a single scab on your tree, you may be able to save it by pruning or removing the branch. If there are several scabs, and if the health of your tree is declining, you should destroy the tree. This prevents the canker from spreading to other citrus trees you may have.

Some sprays and fungicides exist which you can apply to your trees to prevent canker infections. 

Citrus Tree Diseases:  Greasy Spot

Another common disease that can affect your citrus trees is greasy spot. While citrus canker will affect your branches, greasy spot will grow on your fruit and leaves. It takes on the form of black speckling or spots and will produce a greasy oil over the blackened areas. 

Greasy spot is not fatal or as destructive as citrus canker is. You can treat greasy spot by trimming and removing affected leaves and fruit, especially those that have fallen on the ground. You will also want to spray your affected trees with a fungicide that will kill remaining spores. 

Citrus Tree Pests: Aphids

Aphids are a small and relatively harmless pest so long as their population stays at low numbers. However, in large groups, they can eat their way through a large amount of plant matter in a short period. 

Aphids can be hard to spot because of their small size. They gather on the underside of your citrus leaves and will drip an oily substance onto the ground below. 

You can treat an aphid infestation with several types of commercial cleansers, or a mixture of dish soap and water sprayed onto the leaves. You can also introduce natural predators into your garden to cut down their population. Ladybugs are one of the most common predators, and you can buy them in bulk. 

Citrus Tree Pests: Snails

Snails are another common garden pest that can ravage your citrus tree. They will gather all over your tree, from the trunk and branches to the leaves themselves. 

You can remove snails by picking them up by hand and physically placing them elsewhere in your garden. You can also apply physical barriers around the base of your tree to prevent them from getting at your tree, and chemicals like iron phosphate on the soil to do the same.

Learn More About Caring for Citrus Trees

For more information about fighting citrus diseases, or other citrus tree topics, please check out our blog about all things citrus. We have a ton of useful content on all types of citrus trees and plants, including everything that has to do with their care. 

Everything You Ever Wanted to Know About Pruning Citrus Trees

Pruning Citrus Trees

There is a right and a wrong way when it comes to pruning citrus trees. Read on to get all the tips you need to know before pruning your citrus plant.

Like all fruit-bearing trees, citrus trees require regular pruning. Removing branches and growth improves the health of your tree, and ensures that they continue to grow fruit. Understanding the benefits and basics of pruning citrus trees can help you maintain your crop. 

Benefits of Pruning Citrus Trees

Keeping your citrus trees pruned can help their overall health. By maintaining a smaller size, you can keep rows of trees from interfering with each other. 

Additionally, removing branches and leaves improves air circulation and sunlight penetration, which encourages growth and fruit production. Getting rid of plant matter also means that the buds and branches that remain will receive more nutrients, growing larger fruits. 

By preventing branches from rubbing against one another, you also prevent fruit from being damaged or falling off the tree. 

How Much Should I Prune?

The exact amount you should remove when pruning a citrus tree will depend on the tree itself. You should consider removing specific parts depending on the age of the tree.

For example, older trees should have their new shoots removed, allowing more nutrients to flow to existing branches. You can remove these by hand, or with hand pruners, depending on their size.

Newer trees should have thinner branches removed so that the stronger and thicker ones can continue to grow. Hand pruners are the best and quickest way to make a clean cut, but you may need larger trimmers for thicker branches. 

You should also pay attention to where the fruit is growing on your citrus tree. If fruit only appears around the edges of your tree, you need to thin the interior branches to allow more air and sunlight in. 

If part of your citrus tree is no longer shaded, you may want to consider covering it with tree paint, available at most hardware stores. This will prevent burning and sun damage until the tree can adjust. 

Removing Diseased Branches

Another common reason to consider pruning your citrus tree is if you have spotted signs of disease. Black spots on your leaves or fruit, yellow scabs on the branches, and peeling bark can be symptoms of health issues.

Have a tree professional diagnose the disease before taking drastic measures. Sometimes, discoloration is nothing more than an aesthetic change. 

However, if your citrus tree has become diseased, you will have to remove the affected branches and leaves. Trim entire branches off of the tree to prevent the disease from spreading. For mature branches, you'll need to make three separate cuts - twice on the branch to remove it and leave a stub, and on the stub itself - to prevent the bark from peeling. 

You'll also need to dispose of any and all diseased plant matter. Leaving it in your yard can allow the disease to spread to other trees.

Learn More About Citrus Tree Care

Check out our citrus blog for more information about pruning citrus trees, citrus disease, citrus tree care, and more! We provide all sorts of insightful guides and articles about citrus trees, fruit, and related topics.

Common Meyer Lemon Tree Diseases

Meyer Lemon Tree Diseases

Is your Meyer lemon tree sick? Discover some of the most common Meyer lemon tree diseases below.

Citrus trees are absolutely beautiful and one of the most popular is the Meyer lemon tree.

If you currently have or are looking to add lemon trees to your garden or landscaping, you want to make sure that you know how to properly care for and protect them. Even citrus trees aren't immune to disease.

If you're worried that your Meyer lemon tree may be sick, you need to check out some of the most common Meyer lemon tree diseases that occur and what you can do about them.

Citrus Scab

Does your lemon tree have areas that look like warts or scabs? It could be infected by one of the common Meyers lemon tree diseases: citrus scab. Citrus scab attacks the leaves, twigs, and fruit of the lemon tree. 

These citrus scab pustules can spread quickly. Trees are most vulnerable during the first three months following the fall of their blossoms. It's important to protect the trees during this time. Applying a copper fungicide regularly during this time will help protect the lemon tree.


Anthracnose is a lemon disease that may affect your citrus tree. This disease causes the leaves to shrivel up and turn dark in color. In just a matter of days after a tree becomes infected, the disease can turn a beautiful tree into a mess. 

You will want to destroy any infected leaves and prune away any dead limbs. 

Armillaria Root Rot

A common Meyer lemon disease is Armillaria root rot. Symptoms of this disease include yellowing leaves, a decline in foliage, and white growths under the bark that smell. 

Depending upon when the tree is diagnosed with Armillaria root rot, you may not be able to save the tree. Once honey-colored mushrooms appear on the bark, it's too late to treat the disease.

Botrytis fungus

After lemon trees are exposed to long periods of rain, it can become susceptible to a disease called botrytis fungus. This disease is presented with gray mold and can spread very quickly. 

Wounded plants are more likely to be affected so be sure you're taking great care of your lemon trees. You will need to remove any affected plants and thoroughly clean between trees to prevent the infection from getting to other plants and trees.

Phytophthora Fungus

Another Meyer lemon tree disease to look out for is Phytophthora fungus. This fungus causes gummosis which is presented as a gummy presence on the surfaces of the lemon tree.

Phytophthora fungus lives in the soil. You will need to remove all infected fruit and leaves from both the tree and those that have fallen off the tree. You will want to follow up with a fungicide to further protect the tree from more damage. 

Get Educated on Lemon Tree Diseases

If you have or plan on having lemon trees, it's important to be educated on lemon tree diseases. You should know how to treat and even prevent these types of diseases so that your trees will thrive.

Are you interested in growing your own citrus fruit trees? Check out our citrus tree care guide for great tips on everything from planning to protecting your trees.