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.

aphids-on-apple-leaf-3_full_width.jpg
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.

how-to-identify-aphids.jpeg
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

getting-rid-of-aphids_full_width.jpg
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!

2021_gardening_calendar_winter_ad.png

Reader Comments

Leave a Comment

Aphid control

The best way to control aphids is to squash them between your thumb and forefinger. Start with the heaviest concentration of the lil buggers and squish away! Wash their nasty guts and carcasses off leaves when you're done. Be careful not to tear leaves. I have a moderate sized garden so I can manage most of it but this method might not work for larger or commercial size gardens unless you have help. It helps if while you're insecticiding them you taunt them by saying, "you're dead now!" or, "you're all going to die!" Get creative with it! Happy squashing!!

Pests

I have these pests on a Carolina reaper plant. I believe it stunted the growth of the fruit. The peppers were very small, smaller than normal and they have already turned red. Typically they grow green to full size then mature to red.

Anyways, curious to know if this type of pest infection is dangerous to the actual fruit. I washed the fruit (pepper) off but unsure if it is safe to consume.

stunted fruit

The Editors's picture

There are a few reasons why pepper fruit can be stunted. For example, if the plant was planted too early, and the blooms were exposed to cool temperatures, then those fruit can be stunted. (Aim for 70 to 80F day temps, and above 55 night temps before planting.) Diseases such as tomato spotted wilt virus can also cause stunting of fruit. If the whole plant is stunted, then it could be cultural conditions, such as too little water or inconsistent application, not enough nutrients, etc. A heavy pest infestation, such as of aphids or whiteflies, can also stress the plant and cause sparse fruiting and stunting of fruit, as well as yellowing/wilting leaves etc. As to whether the fruit is safe to eat–it might depend on the cause of the stunting, and how far gone the fruit is. Sometimes stunting can affect taste/quality, so it would not be worth eating. If there is any doubt as to safety, it would probably be best not to eat it.

please help me...

I have been told that my house is infested with insects and bugs. I have been very sick for months. At first I was secreting a sugary substance from my skin in different areas. I have undergone several different stages. I can't handle this anymore. I have tons of urine and blood tests proving that I am not on drugs. This aphids match exactly what I am going through. I have had the very tiny black ones come out in my urine. This is not a joke, and I truly need your help.

Seek a doctor for your

Seek a doctor for your healthcare, not a gardening forum.

Health Issues

While I agree with the other person who commented about your problem, I think it can be said in a more understanding form. The problem most people have in offering any type of help when someone we don't know is having a health issue is that since we don't know you and other issues that might be going on, we'd hate to be responsible for your health when a doctor should be researching this with you. I hope you find an answer to your misery soon!

Insect control in garden

I have used Johnson’s baby shampoo to control insects in my garden. I mix 2 tbs shampoo to 1 quart warm water and spray infested area, it kills the aphids and keeps them away for weeks, it is the cheapest solution I have ever made and works well.

Caterpillars

Will this method also kill the baby caterpillars and/or the butterfly eggs that are on the leaves also? I have a milk thistle (butterfly plant) that has tons of these nasty things on it and the big ones are killing my baby caterpillars. I want to get rid of the aphids but not the caterpillares. Or eggs.

Bugs on houseplants

I noticed what I believe to be aphids on a couple of tomato plants that I re potted and brought in from outside when the temps got cold. I did a spray of water, dishsoap and cayenne on them, but then I looked at my other plants and a couple seem to have the bugs too. I'm assuming they spread to those because of the tomatoes. So I decided to spray ALL of my plants with that same solution. Now I am wondering if perhaps I did a bad thing by spraying the plants that I didn't notice any bugs on. I guess my question is...does that solution hurt other plants or is it pretty safe to not only get rid of the bugs, but also as a precaution to keep them from crossing over into the others? Thank you.

Bugs on Houseplants

The Editors's picture

Hi Kathy,

As long as the amount of cayenne in the solution isn’t too strong, it shouldn’t hurt the plants. The solution should prevent aphids from moving across to uninfected plants. Also, if you do notice any ill effects, stop applying it immediately.  

Flower pests

Hi
I have been facing this flower pests problem for quite some time.. i have spotted small white insects on the leaves of the plant and these ones dont fly. They slowly retard the growth of the plant and eventually flowers either stop blooming and rot away or they stop forming all together. I cam send the photos . Please help

spotted flower pest

The Editors's picture

Although we are not entomologists, we can certainly try to help you identify the pest. We’d suggest that you send us an email at almanaceditors@yankeepub.com, along with 1 or 2 photo attachments (low resolution, please). If you can, please tell us the approximate size of the insect, the flower type that they visit, your state/province, where you normally see the pests (stem, flower, leaves, under leaves), if they group in clusters or individually, if they are active during the day or night, specific damage (such as holes in leaves, brown patches, fading, wilting), and any other clues that might help. Thank you!

stopping the cycle - ants farming possible aphids

At the start of the growing season I noticed the leaves of my peppers and eggplants were being eaten. I also spotted several ladybugs. Later, when the beans and corn came up I saw mole holes. After a good rainstorm, all was well, no holes in the leaves. Then, on the sunflowers the ants appeared. Hole reappeared, this time on the beans. Everytime I approach the beans or sunflowers I am attacked by ants. I started with a nighttime hard spray of water on every leaf, under and over. This morning I noticed less ants, so I was able to get close enough to the sunflowers to see some yellow spots on the back. I put out some borax ant bait traps at the bottom of the sunflowers and the row of effected beans. Got some neem oil, but the beans are now in blossom. Any suggestions? I can't weed or pick anything if I am being attacked by ants. They bite aggressively!

Getting Rid of Ants in the Garden

The Editors's picture

It sounds like you’re doing nearly everything you can! Borax ant traps are the most effective way to deal with a colony, so you may just have to wait and see if the borax does the trick. Alternatively, you could try using diatomaceous earth (DE), which is a fine powder that rapidly dehydrates ants and other insects. Spread a solid, ½-inch-wide ring of DE around the sunflower stems and bean stalks, as well as any other nearby structures that the ants could crawl up. Apply DE when you know the ground will stay dry for a few days, so the DE doesn’t get washed away. DE is non-toxic, but cover your mouth and nose while applying it to ensure that the fine particles don’t get into your lungs.

APHID CONTROL: July 3, 2017

H202 works well. Also wipe aphids with wet paper towel, spray top & bottom of leaves. Keep close watch & repeat as necessary. Can't post link but quick search will turn up how-to.

Getting of aphids in the rose garden

When you plant marigolds among the roses you will not have aphids! It is as simple as that!

Marigolds and aphids

I'd heard that they'd get rid of aphids, so planted around my roses and tomato plants. Guess what they're loaded with aphids even after spraying with neem and later with garlic

Bait plants

I'm confused about the concept of bait plants. I have seen black aphids in my front yard and my back yard. They seem to love lamb's quarter, which grows as a common weed here. Am I supposed to leave the bait plants in place and treat them regularly so I know where the pests will go and can kill them? Or what?

Bait Plants for Aphids

The Editors's picture

Most gardeners simply leave the bait plants be, but there’s no reason not to periodically get rid of the bugs on bait plants, too. In fact, it’s a good way to provide extra protection for more-valued flowers and vegetables. Avoid using chemical sprays or wipes on bait plants, though, as this might deter aphids and drive them back to your non-bait plants instead.

aphids in roots

A friend gave me a couple of plants and I started to see aphids so I decided to move one of the plants to another location, away from my other plants. I sprayed the plant leaves and stems with soapy water. I thought maybe the aphids could be in the soil so when I removed the plant I also investigated the soil. I was surprised at the number of aphids that were living in the roots of the plant. I now periodically flush my plants with the soapy water. I'm not a dedicated gardener so I still find aphids on occasion so I'm not sure how this is working but I think any treatment should take the roots into account.

Aphids and Flies

Planting Marigolds will take care of aphids. We have a 10 x 16 "Rose Garden" that has approximately 8 -
10 plants that keep them at bay. We plant them at each corner and one on each side. Sometimes I place a few among the plants to make sure they are protected.

And.... Geraniums in containers at each door (larger spaces, i.e. garage door and slider) I may have additional pots for wider openings. Since we started this we have had no (I repeat NO flies in the house!!! My husband - a biologist - thinks it is the leaves and not the blooms. Sometimes the garage door is open for hours. We do not use any harmful chemicals on the lawn and garden so our beautiful little Maltese has the run of the yard!

Aphids on Rough Skin Lemon, Tahitian Lime, Eureka Lemon Leaves

I'm in Johannesburg, South Africa.
What can I use on these trees ?

Critters on your Tahitian Limes (citrus)

Wetable sulphur, neem oil. Organic materials. If you are badly infested, it is a lot of work to stay organic. Bad infestations, I use malathion, but the bees do not like it. Nor do humans. With any insect problem, you need to repeat many times to stop the reproductive cycle. Be steadfast, and re apply after much rain. University of California Davis is an ag school and publishes on the web. My Hawaii farm has your same troubles. Repeat applications to stop the reproductive cycle. Also spray the ground around the trees. Then the critters do not have a home anymore. Good luck

Aphid control on plants!

There is a GREAT!! Product, that I never see mentioned on any site, that is considered to be, and can be used as organic! It's made from the Chrysanthemum Daisy flower. Its called, "Hi Yield Garden, Pets, and and Livestock Dust", and I swear by it!! It knocked out my aphids AND the fungus gnats in my potted indoor pepper plants!? Totally! To control aphids, spray plants well, with water stream to knock them off. Then, I sprinkled on soil AND plant leaves both, and started bottom watering too. Before applying dust, I also watered potted plants with peroxide (5 percent), and water, as a soil soak to kill any larvae in soil, first.( One part peroxide to 4parts water.) Reapply dust every few days and carefully follow directions, AND read ENTIRE label BEFORE using! Take precautions as some people could be allergic or have breathing problems like asthma! Always wear dust mask! Reapply until you haven't seen your target pest(s) for 2 weeks or so. Yes. It is used on pets, and Livestock to control flies, fleas, etc. It's THAT safe! And it works! Please try, esp. if you want to stay organic! Check label if you buy a diff. brand of a pyrethrum based product, as it may contain butoxyl, which is NOT organic and unsafe! Hope this helps someone else. Good luck!

did you snort this dust? it

did you snort this dust? it clearly says on all high yield products that they are insecticide and not flower products..and they kill bees, which we are losing too quickly as it is!

Aphids attacking summer squash and pole beans

Over the last couple years, I've had aphids wipe out these flourishing crops. Once they get started, there is no stopping them. Insecticidal soap, neem oil, hand picking, shop vacuum and blowing them off with the hose only delays the inevitable. I prune off the most invested leaves but I cannot stop them. By mid-season I have to pull the plants. I will try flour dusting and adding alcohol to the soap solution but I'm skeptical. Is there some way to stop them before they get started?

aphid troubles

The Editors's picture

How frustrating! Have you tried to attract beneficials to your garden? These may help to keep the populations down a bit. Try planting some flowering groundcovers around the perimeter of the garden and order some beneficials such as lady beetles and release them in the area. Silver-colored reflective mulch helps to repel aphids, and using row covers early in the season helps to protect seedlings. Good luck!

Give Aphids the Bait and Switch

The *easiest* thing to do is grow a bait plant or plants that will draw aphids out of your valuable crop. Depending on the size of your grow, either line the perimeter of your garden with the bait plants or keep one or two in the corner of your growing area. I don't know what you're using as far ar fertilizer and/or additives but I don't use ANY nitrates in my garden.

Still, feed your bait plants with Blood Meal: they'll grow really tall, really fast yet have really thin cell walls (sending off infrared struts to insects). I also root drench and foliar with chitin found in crab and shrimp shell. Doing this could prevent insects all together, Chitin provides a bulletproof vest for your plants, you'll definitely notice...so will the bugs, they'll be on the hunt for an easier meal (infrared). They'll head straight for the bait plant(s) and leave the rest of the crop alone. Seriously.

Aphids

The soapy mixture with hot sauce plus some salad oil (spray adheres to plants) also works not only for aphid, but as a deer repellant.
North Carolina US

Black aphid infestation on garlic!

For the first time, in early January I found black aphids all over a small area of garlic. I fought with insecticidal soap and eventually that plus snow seemed to stop them. But they have now moved to a larger bed and are covering the garlic there. Insecticidal soap hasn't touched them there. I've switched to Neem oil but it doesn't seem to be slowing them down. I'm thinking of adding alcohol to the Neem and water to try that but am running out of options. Any other thoughts?

Pages

FREE BEGINNER'S GARDEN GUIDE!

Sign up for our email newsletter by entering your email address.

BONUS: You’ll also receive our Almanac Companion newsletter!

The Almanac Webcam

Chosen for You from The Old Farmer's Store