Aphids on a lemon tree are causes a host of problems, like yellowing leaves. These insects attack young and weak lemon plants, surrounded by aphid-attractive weeds, and those in areas without aphid predators.Aphids on Lemon Tree

You can control aphids by pruning the affected branches, picking and killing the insects, or spraying insecticidal soap.

Causes of Aphids on Lemon Trees?

The causes of aphids on lemon trees are due to high nitrogen levels in the plant, and the lack of natural predators to feed on them. Aphids can also result from young lemon tree leaves and tender foliage, weakened plants, weeds, and attractive plants in the surrounding and warmer climates.

– High Nitrogen Levels

Citrus plants have more nitrogen than any other nutrient for growth, which can be a disadvantage. This is because aphids are more attracted to areas with higher nitrogen levels. The nutrient supports rapid plant growth, meaning new leaves will be produced, which are food for aphids, and you must also know that the constant food supply leads to fast aphid reproduction.

A major nutrient for growing lemons is nitrogen, and when you excessively supply a lot of nitrogen, it can be a door for the aphids to increase. The nutrient is an essential component of chlorophyll, which plants use in photosynthesis. Photosynthesis produces sugar and energy used in plant growth, and this sap is what attracts these pests easily and in detail.

On the other hand, while supporting plant growth, high nitrogen levels also attract aphids, in such a matter, these insects are, therefore, highly likely to invade your citrus. Besides, since the nutrient supports plant growth, new leaves are constantly produced, food for the white bugs. So the key cause of high nitrogen levels can be from the soil or due to the overuse of nitrogen fertilizer.Causes of Aphids on Lemon Trees

– Lack of Predators

And have you heard about predators? There are aphid predators that keep the insect population in control, and lack of them can be a reason for aphid infestation in your garden. These predators could be ladybirds or rove beetles.

Not all insects are destructive, but keep in mind that some insects, like ladybugs, are beneficial because they help to control the aphid population. And a primary reason you could be dealing with aphids in your citrus garden is the lack of these aphid predators.

Aphids will reproduce faster if your garden doesn’t have ladybugs and other insect predators. The presence of these insects controls the aphid population by feeding on them. However, these beneficial insects are rare in citrus gardens because they don’t like the smell of citrus, mint, and cloves.

Also, although they have many benefits, ladybugs have some downsides. They can bite when threatened and release a smelly fluid when they die. These insects also cause stains on fabrics.

– Young Lemon Tree Leaves

Different reasons cause aphids on lemon trees. First, these destructive white bugs mainly feed on young trees with new and soft leaves. Therefore, they are more likely to attack young citrus trees or seedlings to feed on the growing leaves, as they come when they are attracted to the tender foliage that is newly growing and still fresh in chlorophyll.

You would notice that the young citrus leaves are attractive to aphids because they are soft and easy to feed on. These tiny insects have a weak mouthpiece that can only pierce through young leaves, so they mainly concentrate on citrus seedlings.

And since these young plants don’t have a defensive mechanism, the insects could feed on the entire plant, causing its death. While the aphids are hard to notice early, look for signs like stunted growth, plant weakness, or yellow leaves when you see that the young lemonAphids on Lemon Tree Solved

– Weak Plants

The other reason for insect attack on your lemon tree leaves is weak plants. Lack of or too much water can cause plant stress, weakening its ability to fight pests and diseases. Therefore, you can keep your lemons from aphid attacks by ensuring they are healthy and get all the growth requirements.

In short, regarding plant weakness, stress is another cause of aphid and tree disease attacks. Tree stress can be caused by poor watering, like overwatering, and even when there isn’t enough irrigation, the lack of enough sunlight and poor soil conditions would weaken the plant and cause it to hinder its growth.

Aphids on indoor lemon trees are common because these plants are not exposed to optimal growth conditions. Besides, there are fewer aphid predators indoors to control the insect population.

– Weeds and Other Aphid-attractive Plants

Another primary reason for aphid attacks is the presence of plants that attract aphids near the garden. You will likely get aphid infestations if your lemon garden is near a woody forest. In addition, you may also notice that it can be caused by some weeds growing in the garden can be hiding places for aphids, and the tiny insects will soon migrate to your citrus.

If your citrus trees grow near an aphid-infested forest, you will likely suffer aphid problems. These forests grow many aphid-attractive trees that host the insects, and they can easily migrate to your garden, and this way, they can infest your citrus tree.

Also, letting weeds grow in your citrus garden can invite aphids. The insects are also attracted to other vegetables like cabbage, spinach, and potatoes. Besides, weeds and other plants also contribute to plant stress by competing for water and nutrients, making them vulnerable to insect attacks.

– Warm Climate

Citrus plants mostly grow in tropical areas with a warm and favorable climate. Unluckily, most pests like aphids and citrus leaf miners are also attracted to warm temperatures. Before choosing to grow your trees, ensure there are no pests, because they are quickly drawn to growing in such a variation as it will encourage them to reproduce quicker.

How To Get Rid of Aphids that Infest Lemon Trees?

To get rid of aphids that infest lemon trees, you can start by using some water on them or use insecticidal soap, and introduce beneficial insects. In addition, you can also prune away the affected branches, tackle using neem oil, grow aphid-repelling plants, and use pesticides.Solutions to Aphids on Lemon Tree

– Use Water

Using water in a hose pump is one of the natural ways to remove aphids, and you must also be keen that this is a non-chemical yet effective aphid control method with minimum side effects. The technique requires you to spray the upper and underside of the citrus leaf with water at a higher pressure.

However, ensure the pressure setting is manageable to break the branches and this way, you can kill aphids using water. You must stream them off your plant and aim to tackle them, this is best when they haven’t been heavily infested yet.

The high-water pressure from the sprayer pump sweeps the tiny insects away and drowns them. It can also be used to remove other indoor lemon tree pests. But, ensure you allow the ground to dry before the next water spray to avoid overwatering your lemon plants.

– Use Insecticidal Soap

You can make a homemade spray for lemon trees using water and dish soap to control the aphid population. The soap is a non-toxic aphid control method because it has fewer chemicals, and this way, you should start to spray on them.

The soap kills aphids by suffocating them. When it comes into contact with the insect’s cellular membrane, it removes the protective coating reducing its ability to breathe. Removal of the layer also causes dehydration in the insect, hence its death.

This pest control method is cheap and easy to use, and you can easily make it at home with the available items. When spraying the soap, ensure you target the leaves and branches’ upper side and underside.

– Introduce Beneficial Insects

You can also use biological control methods like introducing beneficial insects. These feed on destructive aphids and can also help eradicate other pests. Beneficial insects include ladybugs and green lacewings. On the other hand, you must also remember not to breed some ladybugs because they don’t like the scent of citrus.

– Prune the Affected Branches

You can cut off the affected branches if the aphid infestation is too high on your lemons. Higher insect populations are harder to control, and they could lead to worse diseases that spread to the entire tree.

Once you cut off the branches, dispose of them in a sealed plastic bag and burn them so that they wouldn’t jump on the next tree that is good to infest upon. You should then treat the branches with pesticides to prevent more infestation. Before pruning, ensure you have clean, sharp, and disinfected tools to avoid infecting the plant.

– Use Neem Oil

When looking at how to get rid of black citrus aphids, you could use neem oil, a naturally excreted oil that comes from the seeds of the neem tree. The oil is a safe aphid removal method that works like soap. Applying this oil on aphids covers their bodies and blocks the breathing pores, leading to suffocation, as you dilute it with a few drops of soap and a lot of water.

The advantage of this oil for aphid eradication is that it doesn’t kill beneficial insects. Besides, the oil can kill other unseen pests on the plant to prevent further damage.

– Grow Aphid-repelling Plants

You can prevent aphid infestation in your lemon garden by growing anti-aphid plants. Most of these plants have a strong scent that discourages insects. These can be onions, basil, chives, and garlic. However, you must also consider the compatibility of the plants with citrus trees.

Avoid growing plants with large leaves near lemon trees because these tend to attract insects. Some of these are broccoli, lettuce, and potatoes. The bugs hide in the big leaves and can migrate to your lemon garden.

– Use Pesticides

If the other aphid-control methods didn’t work, consider using pesticides to remove aphids. This is a more effective method, although most farmers are reluctant to use it because of the environmental effects.Pesticides for Lemon Trees

Commercial pesticides have strong chemicals that require leaving the lemons for some days before harvesting. They are primarily used in commercial lemon growing and in highly bug-infested areas.

Some pesticides require mixing chemicals in given proportions, so you could need a professional to apply them. You can also make organic pesticides at home by mixing dish soap, cayenne pepper, and water, and then spray on the pests with all ease.

– Kill Them with Your Hands

If you notice a small aphid infestation in your citrus garden, crush them between your fingers. This is a natural insect eradication method that works best with low populations. You may use your fingers as you catch them and as they can be handy in destroying the insects and dropping them in the garbage bin.

However, don’t crush the insects between the tree leaves; just pick them up and apply pressure on them. The friction destroys the leaf cells and can lead to injuries. Also, ensure you wear gloves when crushing these insects, but if the infestation is too high, this method will only work if it is time-consuming.


Aphids cause lemon tree pests and diseases, but there are ways to control them, and from this article, you will find out that:

  • Weak lemon plants, like those lacking water, can be the reason aphids infest your garden.
  • A lack of aphid predators, high nitrogen levels, and weak plants causes aphids on lemon trees.
  • Lemon growers can control these destructive insects by spraying them with water, using essential oils or pesticides.
  • You can use natural, biological, or chemical methods to control aphids in your lemon garden.
  • You can prune the affected lemon branches if all the aphid control methods don’t work; however, use pesticides if the infestation is high.

The aphid control method you choose depends on how heavy the infestation is, so if you notice aphid infestation early, consider the natural ways to control the insects, like killing them with your fingers.

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