How to Get Rid of Aphids

spider on aphid

Have you ever checked on your garden plants, only to notice how shriveled, yellowed, and deformed they are, despite your best efforts? If so, you may have an aphid infestation. Don’t freak out, though–– we’ll show you how to get rid of aphids.

Aphids invade gardens, sucking the juices out of plants and leaves, causing them to turn yellow and curl. They cause major headaches across the country, so knowing how to recognize and remove them can go a long way. We compiled a list of solutions to evict these critters from your garden.

What are aphids?

Also known as plant lice, aphids are wingless, soft-bodied insects. They are tiny (adults are under 0.25 inches long), have pear-shaped bodies, and come in many colors: white, black, brown, gray, and even pink! They have small antennae and use their strong legs to jump from place to place.

The most troublesome aspect of aphids is how quickly they multiply. New aphids mature in about a week, enough time to produce as many as 80 offspring.

Luckily, aphids move slowly, so they’re easy to remove. However, with how quickly they multiply, you might need to apply your removal method several times before the entire population dies. 

How to get rid of aphids

As problematic as aphids are, there are plenty of simple solutions to kick them out of your garden. Pick at least one of the following methods, but regardless of your choice, you must apply it multiple times over a few weeks to get the desired results. Consistency is key.

Additionally, you want to apply your chosen method early in the invasion–– if you wait too long, the aphid population will increase to unreasonable levels.

Spray with a hose

water  hose
A garden hose is an easy way to spray away aphids
Brenda Ryan

Considering this method’s simplicity, you might think there’s a catch, but believe it or not, one strong blast from the hose can knock aphids off the plant. Since they move slowly, they’ll unlikely find their way back.

This method works best on plants that can handle high water pressure, so if your damaged plants are younger and more delicate, you might want to try a different method.

Insecticidal soap and oil sprays

Aphids are susceptible to soaps and oils due to their soft bodies. The chemicals damage their membranes and suffocate them. When using this method, follow the label instructions and regularly apply it during a heavy infestation (as aphids multiply quickly).

Only spray the colonies directly and not the entire plant. Also, ensure the plant is wet before spraying, as, unlike other pesticides, insecticidal soap stays on the plant and becomes ineffective once dry.

Aphids don’t like strong scents, so adding a few drops of peppermint, neem oil, lavender, clove, eucalyptus, rosemary, or thyme can make your spray even more potent.

Diatomaceous earth

Diatomaceous earth (DE) is a non-toxic powder that dehydrates aphids by removing their shell’s outer coating. Sprinkle DE on the soil around the affected plants, or spray/dust the DE on the plants directly to kill the aphids.

There are two types of DE: food grade and filter grade. You want to use food grade DE to kill the aphids, as filter grade is only used for water filtration. 

Though DE doesn’t harm larger animals, it harms pollinators and other beneficial insects, so don’t apply it where these friendly critters are active. 

Tip: Moisture washes away DE dust, so reapply the DE after rainfall.

Natural Predators

aphids ladybug
Greyson Orlando | Wikimedia Commons | CC BY-SA 3.0

Natural predators like ladybugs, lacewings, syrphid fly larvae, and soldier beetles all eat aphids, while parasitic wasps lay their eggs inside aphids, killing them. 

Though there are processes to attract predators to your garden, you can also manually buy and release beneficial insects. For example, you can buy live ladybugs on Amazon. 

How to prevent aphids

Now that you know how to get rid of aphids, your next step is to apply methods to keep them from returning. 

Predators

Not only will natural predators help remove aphids, but they’ll help prevent aphids from infesting your garden in the first place. Attract birds, lacewings, and parasitic wasps to your garden by giving them an environment with flowers, food, and water.

Incorporating plants that produce food for natural enemies helps keep the predators in your garden. For example, Queen Anne’s lace, coneflower, and goldenrod all provide pollen and nectar for various aphid enemies, including hoverflies and green lacewings.

Companion planting

Companion planting is where two plants are grown in a way that each benefits from the other’s presence. Aphids don’t like strong smells, so growing plants with scents that deter aphids, like marigolds, catnip, garlic, and peppermint, next to plants aphids like to eat will help deter them.

Row Covers

Aphids can’t attack your plants if they don’t have access to them. Thus, protecting your plants with floating row covers will keep the aphids away while still allowing in what the plants need to survive, like water, sunlight, and air.

Set up the row covers as soon as the plants start to sprout and before the insects arrive: the sooner, the better.

Keep plants healthy

Plants with adequate supplies of food, water, and light can fend off aphids more easily than sickly plants, so keeping your plants healthy wards off the aphid army. Don’t overfertilize your plants, and use slow-release or organic fertilizers to keep your plants from overdosing on nutrients.

Ant management

Ants feed on the honeydew aphids excrete while protecting the aphids from natural enemies. If you see ants climbing around your garden, the last thing you want is for them to protect a pasture of aphids. Keep your ant infestations in check to help prevent the aphid population from growing.  

Signs of aphids

green insect
Unsplash

Aphids feed on plant sap, and particularly gravitate toward new growth. The following signs are clear indicators of their presence:

Weakened plants: If you see any grotesque-looking leaves, aphids may be eating them. Check the undersides of leaves, as aphids like to hide there.

Honeydew: Unlike the delicious fruit, this honeydew is a white sticky substance aphids produce as waste. As aphids eat leaves, they digest the sugars. What they don’t digest becomes honeydew, which can lead to…

Sooty mold: If branches and leaves look black, it’s a result of fungal growth caused by the honeydew.

Viruses: Aphids may transmit viruses, infecting fruits and vegetables and causing leaves to curl and turn yellow.

Ants: If you see ants around your garden, it may signal an aphid infestation. Ants and aphids have a mutual symbiotic relationship: aphids feed the ants honeydew and the ants protect the aphids in return. 

FAQ about aphids

1. How many species of aphids are there?

There are about 1,350 species of aphids in North America and 5,000 worldwide.

2. What types of garden plants should I protect from aphids?

Young plants are more susceptible to damage, so focus on new growth in your quest to control aphids.

3. How long is an aphid’s life span?

The average lifespan of an aphid is approximately one month.

Aphids suck (literally)

Having an aphid infestation isn’t fun, but it only takes a few simple solutions to get rid of these little buggers. Aphids don’t pay the rent, so why should you let them stay in your garden for free?

If you don’t want to kick these pests out on your own, hire a professional gardener to handle them.

Main Image Credit: Ivan Radic | Flickr | CC BY 2.0

Stuart Kushner

Stuart Kushner is a writer and aspiring product designer based in New York City. When he isn’t doing either, Stuart enjoys heavy metal music, exercise, and trying new food and drinks.