Aphids

How to Identify and Get Rid of Aphids

Aphids
Pixabay

What are those little green bugs on your plants? They’re probably aphids! Here are our best tips on how to identify and control aphids in the garden.

What Are Aphids?

Aphids seem to find their way into every garden. They are small, soft-bodied insects that feed by sucking the nutrient-rich liquids out of plants. In large numbers, they can weaken plants significantly, harming flowers and fruit. Aphids multiply quickly, so it’s important to get them under control before reproduction starts. Many generations can occur in one season.

The good news is that they tend to move rather slowly and aphid control is relatively easy.

Identification

Identifying Aphids

Aphids are tiny (adults are under ¼-inch), and often nearly invisible to the naked eye. Various species can appear white, black, brown, gray, yellow, light green, or even pink! Some may have a waxy or woolly coating. They have pear-shaped bodies with long antennae; the nymphs look similar to adults. Most species have two short tubes (called cornicles) projecting from their hind end.

Aphid
A close-up view of a rose aphid.

Adults are usually wingless, but most species can develop a winged form when populations become crowded, so that when food quality suffers, the insects can travel to other plants, reproduce, and start a new colony. Aphids usually feed in large groups, although you might occasionally see them singly or in small numbers.

While aphids in general feed on a wide variety of plants, different species of aphids can be specific to certain plants. For example, some species include bean aphids, cabbage aphids, potato aphids, green peach aphids, melon aphids, and woolly apple aphids.

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Some aphids are darker colors, like brown. The potato aphid is a common brown aphid. Photo credit: GrowVeg.com.

What Does Aphid Damage Look Like?

Nymphs and adults feed on plant juices, attacking leaves, stems, buds, flowers, fruit, and/or roots, depending on the species. Most aphids especially like succulent new growth. Some, such as the green peach aphid, feed on a variety of plants, while others, such as the rosy apple aphid, focus on one or just a few plant hosts.

  • Look for misshapen, curling, stunted, or yellowing leaves. Be sure to check the undersides of leaves; aphids love to hide there.
  • If the leaves or stems are covered with a sticky substance, that is a sign that aphids may have been sipping sap. This “honeydew,” a sugary liquid produced by the insects as waste, can attract other insects, such as ants, which gather the substance for food. When aphids feed on trees, their honeydew can drop onto cars, outdoor furniture, driveways, and so on.
  • The honeydew can sometimes encourage a fungal growth called sooty mold, causing branches and leaves to appear black.
  • Flowers or fruit can become distorted or deformed due to feeding aphids.
  • Some aphid species cause galls to form on roots or leaves.
  • Aphids may transmit viruses between plants, and also attract other insects that prey on them, such as ladybugs.

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Aphids can be various colors, including yellow, and produce a sticky honeydew substance. Photo Credit: John Obermeyer/Purdue University.

Control and Prevention

How to Get Rid of Aphids

  • Try spraying cold water on the leaves; sometimes all aphids need is a cool blast to dislodge them. Typically they are unable to find their way back to the same plant.
  • If you have a large aphid invasion, dust plants with flour. It constipates the pests. 
  • Neem oil, insecticidal soaps, and horticultural oils are effective against aphids. Be sure to follow the application instructions provided on the packaging.
  • You can often get rid of aphids by wiping or spraying the leaves of the plant with a mild solution of water and a few drops of dish soap. Soapy water should be reapplied every 2-3 days for 2 weeks.
  • One variation of this soap-water mix includes cayenne pepper: Stir together 1 quart water, 1 tsp liquid dish soap, and a pinch of cayenne pepper. Do not dilute before spraying on plants.
  • Diatomaceous earth (DE) is a non-toxic, organic material that will kill aphids. Do not apply DE when plants are in bloom; it is harmful to pollinators, too.

How to Prevent Aphids

  • For fruit or shade trees, spray dormant horticultural oil to kill overwintering aphid eggs.
  • Beneficial insects, such as ladybugs, lacewings, and parasitic wasps, will feed on aphids. Supplemental populations of these insects can be ordered online and should help keep the aphid populations controlled from the start.
  • Companion planting can be very helpful to keep aphids away from your plants in the first place. For example:
    • Aphids are repelled by catnip.
    • Aphids are especially attracted to mustard and nasturtium. Plant these near more valuable plants as traps for the aphids. (Check your trap plants regularly to keep aphid populations from jumping to your valued plants.)
    • Nasturtiums spoil the taste of fruit tree sap for aphids and will help keep aphids off of broccoli.
    • Garlic and chives repel aphids when planted near lettuce, peas, and rose bushes

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Hosing down your plants is one way to control the aphid population in your garden.

Using Alcohol to Control Aphids

Isopropyl alcohol (also called isopropanol or rubbing alcohol) works fine and is easy to find, but be sure it doesn’t have additives. Ethanol (grain alcohol) seems to work best. Alcohol usually comes in 70 percent strength in stores (or 95 percent strength purchased commercially). To make an insecticidal spray, mix equal parts 70 percent alcohol and water (or, if using 95 percent alcohol, mix 1 part alcohol to 1 ½ parts water). 

You can also add alcohol to a soapy emulsion to make it more effective. For example, in a spray bottle, combine 5 cups water, 2 cups alcohol, and 1 tablespoon liquid soap.

Caution: When applying an alcohol or soap spray, or a combination, always test a small area first, and apply in morning or evening, when the sun is not beating down. Watch the plant for a few days for any adverse reactions before applying more. Plants can be sensitive to alcohol and soap. Also, some soaps have additives that can damage plants—select the purest form.

Check out this video to learn more about how to get rid of aphids. 

Do you have more tips for controlling aphids? Let us know in the comments below!

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Reader Comments

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How do you make the Garlic

How do you make the Garlic solution? I noticed some tiny little dark colored bugs or beetles on my Cranberry Butterfly bush, was thinking they could be baby ladybugs but not sure. Then I seen your comment here and thought hmmm could be tiny flee beetle but I do not know what those look like! Also if I use the Garlic solution you suggested will it harm the Ladybugs? or their babes? or will it harm the Monarch Butterfly? or Monarch Caterpillar? Or harm any other Butterflies or Butterfly Caterpillar? Also wondering if you know why my Sunshine Blueberries, and my Chandler Blueberries, leaves are turning brown and crisp and leaves dying. Also have already lost 2 of my Sunshine Blueberries to this and getting ready to lose a 3rd and last one. Need Garlic solution recipe Please, and is Garlic solution OK to use on my Butterfly bush and my Blueberry bushes. Please....reply Almanac staff. Thank you for any help you can offer.

To make a garlic solution to

The Editors's picture

To make a garlic solution to combat aphids, mince a few cloves of garlic into 2 teaspoons of mineral oil. After a day, strain out the garlic pieces and add what's left to one pint of water. Add one teaspoon of liquid dish soap. When you apply the solution, you can dilute it down with water in a spray bottle (about 2 tablespoons garlic to 1 pint water). It's organic and safe.

Also try 1% Ceylon Cinnamon

Also try 1% Ceylon Cinnamon Leaf Oil mixed with 99% water, sprayed on the plant with a pump sprayer (Home Depot $9.99). However you should first wash your plants with the hose set at firm pressure to wash away as much of the mold (created as a result of aphid honey dew droppings) and aphids as possible. Then spray the whole plant and a little Cinnamon Oil at the base of the plants to stop the ants that also come to eat the honey dew created by aphids. Ceylon Cinnamon Oil is a powerful mold killer and safe to eat. But dilute, otherwise it will burn the plant leaves.

I was managing aphids until

I was managing aphids until recent heavy rain followed by high heat. I pulled all my infested plants carefully ( kale & tomatoes) , but the aphids are ALL OVER the soil. How to rid them there? I live in Colorado, 6100 ft., zone 5. I would prefer an organic solution. Thank You!

Aphids do like kale. knock

The Editors's picture

Aphids do like kale. knock them off with sprays of water. Organic insecticides that are effective for aphid control in vegetable gardens are insecticidal soap, pyrethrin, and neem oil. Apply in mornings all over every side of leaf.

Aphid Removal Success! I live

Aphid Removal Success!
I live in Colorado and my huge tree gets infested yearly. I be tried everything from organic to (finally) toxic solutions. The tree was too large and dense to stop the infestation. Now I purchase two small bags of ladybugs from my local nursery (maybe 2,000 in each?), sprinkle cola on the area around the base of the tree, and release them at dusk. They stick around until the aphids are gone and then fly away! The neighborhood kids all come out and we read ladybug books before the release. It's an annual event!

If you need some good

If you need some good insecticidal soap check this store they have a lot of organic solutions for aphids!

http://www.jarrodspestcontrols...

If you plant a row of tobacco

If you plant a row of tobacco away from your tomatoes you will find that the aphids and other pests will eat the tobacco instead of your tomatoes
http://www.youtube.com/watch?v...

The photo is misleading as

The photo is misleading as most aphids you will encounter will not have wings. Also, most aphid species DO discriminate between plant species (well plant Families anyway), and most will NOT go from plant to plant. Most often only the flying stage of the insect will go to another plant. Cabbage aphids for instance WILL NOT infect roses. There are a few species that are indiscriminate too, so you should know your insects.

Thank you for bringing this

The Editors's picture

Thank you for bringing this to our attention. We have revised the text and will look for a photo that shows a more typical adult form.

A botanist who was our TV

A botanist who was our TV weatherman, Harry Volkman, in OKC some 50 years ago gave us gardening tips when he did the weather show. He said: "To keep the pests, such as aphids, off your tomato plants all you have to do is break a large branch down close to the ground. DO NOT BREAK IT OFF, just break it and let it hang and stay there. The plant will then emit a chemical that the pests such as aphids do not like and will stay away from your tomato plants."

So have you tried that & has

So have you tried that & has it worked for you?
Maybe the plant no longer smells like food?

My tomato is starting to get

My tomato is starting to get aphids. I have used some plant bug sprays, but not heavily because a ladybug has laid her eggs on my plant. Is there anything else I could use to get rid of the bugs?

It sounds like you have the

The Editors's picture

It sounds like you have the best solution already. Ladybugs eat aphids.

That's unfortunate... Your

The Editors's picture

That's unfortunate... Your treatment of aphids is one of the recommendations, but the wilt is not necessarily a result. The wilt pathogen is seed and soil borne; it might reside in the soil. (There are a couple of kids of wilt, btw). Once a plant "catches" the wilt, it is difficult to recover from it.
You can try to grow tomatoes this year. Rotate them: plant them in another spot or in new soil, if you use a pot. In each case, amend the soil with healthy compost. And buy resistant cultivars; the plant tags will indicate this, or ask the nursery attendant. We hope this helps.

Last year, 2012, my tomatoes

Last year, 2012, my tomatoes suffered a bad infestation of aphids. I washed them many, many, many times gently with the hose. Didn't work...then all the plants had bacterial wilt....couldn't get that stopped and then the high heat! I am wondering if washing them so many times and all the splashing at the bottom caused the wilt. I had cut the leaves off at the bottom up at least 12" but still were infected. Any ideas?? I also am wondering if I should plant tomatoes in that garden again...I don't have many options to rotate. Hope this year is better. Thanks

How to grow large tomato -)

How to grow large tomato -)

They were probably in the

They were probably in the tree long befroe you built your tree house. Sounds like you need a strong ant and roach killer. We had a tree house growing up and had to put up with wasp's nest and everything else that crawled and flew. My brother got bit by a spider, and that was the end of out tree house days. The only things you can do is spray the whole place with an ant killer. Good luck.

If you want a butterfly

If you want a butterfly garedn you'll just have to learn to live with the bugs. Any insecticide that kills or repels another bug will do the same to a butterfly. Why not get a good insect identification book and learn to recognize and appreciate the variety of creatures that are attracted to your butterfly garedn. Was this answer helpful?

Ants farm Aphids like we

Ants farm Aphids like we raise cows. Get rid of the ants and usually you will also get rid of the aphids.

Many know that ants milk

Many know that ants milk aphids. What most don't know is how to get rid of the ants in a safe, non-chemical way. Any known remedies for this?

Unless you have fire ants, we

The Editors's picture

Unless you have fire ants, we would recommend you try to live with ants as they manage pests and do good work. However, if you can not co-exist, you could use beneficial nematodes. Also, borax and sugar (1/2 and 1/2) mixed with water to a thin paste is something that may work. Put it in mall shallow dishes close to where you see the ants (keep it away from pets and small children if possible). The ants will eat the mix, bring it back to the nest and eventually kill the entire colony.
Pour boiling water over the nest, or sprinkle coffee grounds over the hill.

I just dug into red ants in

I just dug into red ants in the garden. Do you have any suggestions for getting rid of them?

TANGLEFOOT is a sticky gel

TANGLEFOOT is a sticky gel put around tree trunks to keep ants from getting to the aphids in fruit trees. Works great.

Plant a mint-leaf plant where

Plant a mint-leaf plant where ever you are having this problem. You may also just clip some leaves and set on top of ants, or boil some leaves in water and pour over area. Works for me. Good-Luck.

I use grits. the ants will

I use grits. the ants will eat the grits and drink water and they swell and die. I learned this from a AC tech, ants had gotten in our ac once and he used grits and it killed them. so now I use grits for ant beds too. works very well as long as they get water in a day or two afterwards sprinkling grits on them.

Cinnamon is a great natural

Cinnamon is a great natural ant repellant I sprinkle a little on my inside planets I'm going to try that outside this year I did not know ants were bad for plants ... But that explaines a lot now.

The best way to prevent

The best way to prevent aphids is to plantmarigolds every where u can

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