How to get rid of aphids on trees

Your trees look fine, then one day you start to notice the leaves wilting and new growth being stunted. You take a closer look to see what is causing your trees' troubles. Without knowing it, aphids have seemingly moved in overnight and taken over your trees.

How do you get rid of these pest and save your trees? We will delve into some ways to take control of this unwanted colonization of aphids and how you can prevent it from happening again.

What are aphids?

Aphids are some of the most common pests that attack plants. These insects are members of the superfamily aphidoidea. They feed on plant sap causing damage and eventually death to the plants they infest.

Also called blackfly or greenfly, aphids occur in colonies. There are more than 5,000 species listed in the aphididae family, 400 of which are found on fiber and food crops. They are common problems in forests, farms, and gardens.

Aphids don’t just suck plant sap, they also produce a sugary liquid waste called “honeydew” that serves as the base for growth of sooty molds in infested trees.

Moreover, some species of aphids serve as vectors for plant viruses where they can carry a virus on their mouthparts and infect a plant within just a few minutes.

And because they are capable of asexual reproduction and telescopic development, aphids can easily multiply in numbers, making them very hard to control even with the help of insecticides.

In fact, a female aphid can produce up to 12 offspring daily in warmer temperatures. This is why aphid populations can easily kill younger plants or overrun them within just a week after the infestation starts.

What kind of damage can aphids do to trees?

Infestation begins when a group of winged aphids fly to a tree that makes for a good host. After depositing wingless aphids on this tree, the winged ones move on to find new plants while the nymphs feed on plant sap. They mature within just 7-10 days. Once mature they are capable of producing up to 60 offspring each.

Once this infestation is in full swing, you will start to see some of the most common signs of aphid damage including:

  • A sticky substance on the leaves of trees. This is the honeydew that aphids produce. It is a common sign of infestation.
  • Black leaves and branches that are the result of a fungal growth called sooty mold from the honeydew produced by aphids.
  • Curling, yellow, or stunted leaves that, if you check the undersides, you would see small aphids living on them. Some leaves also get misshapen. You will not notice health new growth on trees in the area of the infestation.
  • Deformed fruits and flowers because of the aphids feeding on them.
  • A slow growth in trees because of the aphids taking away their nutrients and fluids.
  • New growth, flower buds, and flowers could look distorted due to the colonization of aphids.
  • The transmission of viruses from aphids may cause more serious infestations of other insects like ants and ladybugs on trees; causing more damage to them.

Solutions for getting rid of aphids on trees

An aphid infestation is definitely a huge problem, whether it’s in your garden or farm. So before things get out of control and in order to save your tree, it’s very important to manage it properly. Here are some easy ways to get rid of aphids on trees:

Use soapy water

One of the easiest remedies for aphid infestation, especially during its early stages, is to use soapy water. Castile soap is an excellent option for controlling aphids because it doesn’t contain any antibacterial ingredients, fragrance, degreasers, and hand softeners that could cause more damage to your tree.

Never use detergent in your soapy water solution because it doesn’t contain oils or fats that will make it less effective against aphids.

To make your soapy water spray, combine a few tablespoons of pure liquid soap in a small bucket with water. Put some of this solution in a spray bottle. Use it to spray directly on the affected parts of your tree, especially the leaves where the eggs and larvae live.

You can also purchase insecticidal soaps at nurseries to spray on trees that have aphid infestation.

Use vinegar

If you want your soapy water solution to be more effective, you can add vinegar to it to make an all-organic natural aphid spray.

Vinegar is effective in getting rid of insects like aphids for good because it coats the aphids’ body and clogs their breathing mechanism; leaving them to die. Combining vinegar with liquid soap makes the solution more lethal.

A classic recipe for this natural spay includes mixing 1 tablespoon of natural liquid soap, like Castile, and 1 tablespoon of white vinegar in 1 gallon of water.

Make sure to spray all infested parts of the tree, especially both sides of the leaves to not only get rid of the older aphids but also kill their offspring.

Use neem oil

Produced by pressing out the seeds from neem trees, neem oil is one of the most popular organic insecticides today. This is mainly because of its active ingredient azadirachtin that has repellent properties and reduces insect feeding.

Neem oil also contains ingredients that make it hard for insects to reproduce and multiply.

To make your own neem oil spray, you have to add 2 tablespoons of neem oil per gallon of water and mix it thoroughly before transferring it into a spray bottle.

Spray all the surfaces of the tree, especially the affected leaves, to make sure that they are fully soaked. Do this on a sunny day so the rain won’t wash away the solution.

According to experts, it’s best to apply neem oil spray every 7 days on an infested tree to make sure the aphids don’t come back. You can also spray your plants every 14 days as a preventive measure.

Use rubbing alcohol

Rubbing alcohol is another great option for getting rid of aphids on trees without the need for you to buy insecticides. You can pour rubbing alcohol directly into a spray bottle and spray the affected areas of your tree to kill any aphids and their eggs.

If you think that your alcohol is too strong, you can always dilute it with water before using it as your homemade insecticide spray. Rubbing alcohol has been proven to clear your tree of aphids and other infestations without causing any harm to it.

How to keep aphids away from your trees

Proper maintenance is the best way to keep aphids off of your trees. Anyone of the methods listed in this article can be used as a regular treatment to keep aphids off of your trees.

The best solutions are going to be a natural method like organic soap, vinegar, neem oil, and rubbing alcohol. Spray your trees once every three months to keep aphids and other pesky insects off of your trees.

What to do now

Don't let aphids ruin your day and tree. Get a spray bottle and a few ingredients you have around you house to take them down. It's better take act now than to let the infestation to go further. Remember, you may need to spray your trees a few times to fully get rid of the aphids.