Gardening Tips

Pests and diseases of the lemon tree

Pests and diseases of the lemon tree

The lemon tree is a fruit tree widely known in many countries for its delicious fruits, lemons. It is not uncommon to find lemon trees in gardens and even in large pots, and bearing in mind that, like all fruit trees, it is a plant that takes a long time to start bearing abundant fruit, it is worth knowing its weak points well.

For this reason, in this EcologíaVerde article, we have compiled a list of the main lemon pests and diseasesas well as a few tips on how to treat and prevent them.

Lemon pests – names and photos

There are actually several pests that can affect this citrus fruit, but these are the main lemon pests:

lemon miner

It is a miner insect that digs inside the leaves, feeding on them. Its damage is concentrated in the young leaves, and can be recognized because the attacked leaves begin to show yellowish or brown spots and the leaves begin to roll up and fold back on themselves until they finally fall.


Aphids are green insects and very small in size, less than 5 mm. These tend to settle on the buds and flower buds of the plant, feeding on them. In this way, the tree sees its ability to develop new leaves reduced and its fruits appear deformed that make them unfit for consumption or marketing.

cottony mealybug

The cochineal in the lemon tree It is usually seen during the summer, when temperatures are high and humidity is very low. These insects, which are covered in whitish waxy secretions, settle on the stems and undersides of leaves, hiding in groups. It is important to locate them as soon as possible so that they can be easily treated before they become too widespread.

Red spider

This mite is only slightly larger than aphids, although it is easier to spot due to its striking red color and the webs it creates between leaves, allowing it to move across them. It is not one of the most damaging pests, but it feeds on the plant and harms its development. It usually appears in summer, like the cochineal, since it needs dry environments and high temperatures.

Lemon tree pests and diseases - Lemon tree pests - names and photos

Lemon diseases – names and photos

Next, we mention the main lemon diseases.

alternaria alternata

This disease is caused by the fungus called Alternaria. It appears when the risks are excessive and the tree has too much moisture. This is one of the diseases of lemon tree with wrinkled and yellow leavesso when this fungus attacks your leaves they look like this and get worse as the tree weakens, until they turn brown, shrivel and drop.


This is produced by a viroid and causes cracks to appear vertically and scales on lemon tree bark, in addition to dwarfism in young shoots and yellow spots. Once it affects, unfortunately, you can only eliminate all the rest of the attacked tree so that it does not spread to others.

virus of sadness

This is a very serious disease, which in the most extreme cases can kill the lemon tree in a few weeks. Aphids are its main propagators and its range of symptoms is very wide, from the cessation of its growth and weakening until the tree begins to flower at a time that does not correspond to it. As with exocortis, only the affected tree can be removed to prevent it from spreading to others.


It is a type of mold caused by the fungus Penicillium italicum that is usually found on the skin of fallen fruits. The spots are white with different shades of green in the center.


This disease is of the viral type and causes the bark to detach or even show gummosis in some areas of the trunk and branches. The tree can be saved if it is treated in time, although its cure is not definitive. Here we tell you more about Gummosis: what it is and treatment.

Lemon tree pests and diseases - Lemon tree diseases - names and photos

How to prevent and treat lemon pests and diseases

For prevent pests and diseases of citrus fruits such as lemon treeswe must take into account the basic care for the cultivation and maintenance of the lemon tree, ensure that its condition is optimal on a day-to-day basis, surround it with other plants with which protection is achieved, such as lavender or calendula, and continue More tips like the ones you will find in this other guide on How to have a lemon tree without pests and healthy.

Be aware of possible symptoms of health problems in the tree. For example, if your lemon tree shows yellow leaves with green nerves, it means that it needs a greater supply of iron, so you should look for a fertilizer rich in it. If that doesn’t fix it, then the problem is that you’re overwatering it.

To finish, follow these tips for treating lemon tree pests and diseases more common:

  • Against the miner insect, the red spider and aphids, the simplest thing is to spray Neem oil in the affected areas, which will end up eliminating the plague.
  • In the case of the cottony mealybug, you can prepare your own insecticide by mixing one part of water with one part of methylated spirit in a common 1.5-litre bottle and adding a teaspoon of dishwashing soap. Spray the mixture on the affected areas of the lemon tree and it will not take long to finish it off.
  • The case of the fungus Penicillium is easy to treat with fungicides containing copper.
  • Psoriasis can be alleviated by scraping the diseased areas when spring comes to an end and covering the affected area with Zineb.

In addition, we recommend these other articles from EcologíaVerde that will help you have a healthy lemon tree:

  • Citrus pests and diseases and their control.
  • How to combat pests in organic farming.
  • Home remedies to eliminate aphids.
  • Eliminate the cottony mealybug: treatment and home remedies.

Below you can see a video on the care of the lemon tree in a pot, in which you will also find information on the pests and diseases of this citrus.

If you want to read more articles similar to Pests and diseases of the lemon treewe recommend that you enter our category .

About the author


Leave a Comment