It is frustrating to see aphids in your garden, sucking the life out of your plants. If they show up in your garden, you will want to get rid of them in a hurry. Aphids can multiply quickly and then spread to other plants in a single season. It is important to be able to identify aphids and to treat the problem so that you can get back to growing your garden.
So, how do you get rid of aphids? Spraying infected plants with a mixture of water, dish soap, and alcohol is one way to control aphids. Neem oil is another aphid treatment that you can use to spray your plants. You can also use onions, garlic, chives, or orange extract to repel aphids and protect your plants. Using cloches or row covers on young plants will protect them from aphids.
Before you start spraying your plants, it is important to understand what aphids are, how to identify them, and why they are harmful. After we talk about aphids, we’ll get into the details of natural methods you can use to get rid of them without destroying beneficial insects, such as bees.
What Are Aphids?
Aphids are tiny insects that come in many colors. Most gardeners are familiar with green aphids, but they can also be black, white, gray, brown, yellow, or pink.
Some aphids are specific to certain crops, such as potato, cabbage, or beans. Aphids will also infect houseplants if they get indoors.
Aphids are small, often a quarter of an inch or smaller in length. They have a body that looks like an oval.
What do Aphids Eat?
Aphids feed on plants by sucking out the juices. Depending on the variety of aphid (there are thousands!), they may feed on leaves or stems, flowers or fruit, and even the roots of plants.
Aphids tend to prefer tender plants, going after younger, softer growth as opposed to older, harder, woody stems. They tend to congregate on the bottom side of leaves, and usually lay their eggs there.
Why Are Aphids Harmful?
First of all, the appearance of aphids is deceiving. It is tempting to believe that they cannot cause much damage, since they are so small.
However, aphids can multiply quickly, maturing in 7-10 days and giving birth to up to 80 offspring in a week. If there are enough aphids on a plant, they can easily suck up enough juices to stunt the plant’s growth and kill it.
Even worse, aphids can transmit viruses between plants. If even one of your plants (or a neighbor’s plants) is infected with a disease, aphids can carry the infection to other plants when they bite and suck out the juices.
As if that weren’t bad enough, aphids also produce waste that can cause multiple problems. As aphids eat, they excrete honeydew, which is a sugary solution that is a waste product from their feeding. This honeydew can cause sooty mold (a fungal infection) to appear on a plant.
Honeydew also attracts ants, which are known to “tend” the aphids like humans tend cattle or chickens. In a symbiotic relationship, the ants eat the honeydew that aphids excrete, and in exchange, the ants protect the aphids from enemies.
If you go near a plant infected with aphids that are guarded by ants, the ants may attack you by crawling up and biting your neck – I have been there, and it is not much fun.
For more information, check out my article on getting rid of ants in your garden.
The best way to deal with these problems is to avoid aphids in the first place. If you already have aphids in your garden, then here are some ways to deal with them.
How to Get Rid of Aphids
There are plenty of methods you can use to get rid of aphids in your garden. Some of them are completely organic, relying on natural substances (orange extract, for example) that repel aphids.
Spray Plants with Water, Dish Soap, and Alcohol to Control Aphids
This is a quick and easy way to treat plants infected with aphids. First, mix together some water, dish soap, and alcohol. Then, put the solution in a spray bottle.
Go out to the garden and spray plants if you see aphids (remember that they like to hide on the underside of leaves).
Avoid spraying right before a rainstorm, since this will wash away the solution, and you may have to apply it again.
If you don’t like the idea of soap and/or alcohol in your garden, you can try a mixture of water with cayenne pepper as a means of repelling aphids from plants.
Spray Plants with Neem Oil to Control Aphids
Neem oil is another method you can use to spray plants that have been infected with aphids. Neem oil is available in spray bottles online or at your local garden center.
One caution: you should avoid breathing in Neem Oil, so wear a mask when applying it. Also, don’t use it on a windy day. Make sure to follow the instructions on the container.
Spray Off Aphids with a Hose
If you want to go completely natural, you can simply spray off aphids with your garden hose. This method may not keep aphids from coming back, but you can avoid using chemicals in your garden.
This is a good option if your plants are already flowering, since some of the other methods mentioned here can repel or harm bees as well as aphids. Of course, you can always hand pollinate your plants if the bees aren’t doing the job.
For more information, check out my article on hand pollination.
Use Onions, Garlic, or Chives as Aphid Repellent
This is a good natural aphid repellent that is more effective than water alone. When you plant onions, garlic, or chives near plants that you want to protect, the aphids may not want to go near them (this is known as companion planting).
If it is too late in the season to plant, you can also try putting orange extract or banana peels near the plants you want to protect.
Dust Plants with Flour to Control Aphids
Dusting your plants with flour is supposed to constipate aphids, preventing them from secreting honeydew and attracting sooty mold or ants.
As with the spraying methods mentioned earlier, a rainstorm will wash away your flour treatment. Make sure to check the weather forecast so you don’t waste your effort.
Use Cloches or Row Covers to Protect Plants from Aphids
Remember that aphids like to feed on tender, young leaves and shoots, as opposed to older growth. As such, it is younger plants that will need protection from aphids early in the season.
Luckily, younger plants are often small enough to fit inside cloches. A cloche is a small glass or plastic container with a vent at the top that protects young plants from cold, wind, and insects.
A cloche is useful because you can leave the vent on the top open during hot days, and close it to protect plants from cold nights.
You will need to remove the cloche when the plants get large enough, but by then, the tender young growth will be mature enough to resist aphid infestation.
You can also use row covers to protect plants from cold and pests. Instead of protecting one plant, a row cover can protect many plants at once.
Row covers are made of plastic or fabric that is clear to allow sunlight through, and breathable to allow air through (plastic row covers often have small perforations for air flow). Just remember to water underneath row covers made of plastic!
For more information on cloches and row covers, check out my article on protecting your plants from cold and frost.
Use Diatomaceous Earth to Remove Aphids (and Ants)
Diatomaceous earth is a substance that is “sharp” enough to cut the bodies of aphids, ants, and other insects that come in contact with it. The insects then die of dehydration, due to their wounds.
You can dust your plants with diatomaceous earth if they are infected with aphids and ants, or as a preventative measure. Rain or watering will wash it away, so be sure to apply it after you water, and make sure there are no rainstorms in the weather forecast.
One downside of diatomaceous earth is that it does not discriminate between pests and beneficial creatures. It can also kill bees if they come in contact with it. So, avoid using diatomaceous earth if your plants are flowering, since bees will come soon after flowers.
Use Tanglefoot to Capture Aphids (and Ants)
Tanglefoot is a sticky substance that traps aphids, ants, and other insects. You can buy it online or at your local garden center.
As with diatomaceous earth, this substance does not discriminate between pests and beneficial insects, so be careful when you apply it.
Buy Ladybugs to Release into Your Garden
Ladybugs are another natural method of aphid control – one which uses no chemicals. Ladybugs are natural predators of aphids, and will fly around eating them off the plants that are infected.
The ladybugs may not stay around once the aphid population is under control. However, they can help to prevent an infestation or a rapid spread to other plants in your garden.
For more information or to buy ladybugs, check out this article on aphids from planet natural.
Use a Mini Vacuum on Indoor Plants
If aphids have made the transition to the inside of your house, you can use some of the methods mentioned above. However, you can also try to use a small USB vacuum to suck them off of the leaves of your houseplants.
How to Dispose of Infected Plants
In some cases, a plant will be close to death due to aphid infestation. If you think it cannot be saved, it may be worthwhile to pull it out and destroy it to prevent a spread of the aphids to other plants in the garden.
If you take this course, do not put the plant in your compost pile or bin. Aphids can winter over in a compost pile, and you don’t want to be dealing with a bigger problem next year.
Instead, destroy any infected plants (burn if it is allowed, and put the ashes in your compost pile, or throw away the plants if burning is not allowed). For more information, check out my article on putting ashes in your compost pile.
Hopefully, you are a little more familiar with aphids: what they look like, how they can harm your plants, and how you can fight back.
If you have trouble with insects in your garden and want to take an organic approach to combat them, you can learn more about carnivorous plants in my article here.
I hope you found this article helpful. If you have any questions or advice of your own about how to get rid of aphids, please leave a comment below.