Aphids are arguably one of the most common (and frustrating!) pest insects in the garden. Every gardener I know struggles with aphids at some time or another. They are sneaky little buggers and can cause a lot of damage, especially if large populations are left unchecked. Unfortunately, aphids are attracted to a wide variety of plants. However, the good news is that aphids also happen to be one of the easier pests to stop! There are several ways to swiftly get rid of aphids in an organic garden, and keep your plants lookin’ mighty fine.
Read along to learn 9 ways to get rid of aphids on your garden plants. Some options are preventative in nature, such as implementing strategic companion planting. Other methods involve killing the aphids with physical, biological, or “chemical” means. No matter what route you choose, rest assured that all 8 of these aphid control options are organic!
Before we dive into the ways to get rid of aphids in the garden, let’s briefly familiarize ourselves with these pesky little wankers. Also, please keep in mind that an organic garden is not a perfect one. We always have a few aphids hanging around in ours. The goal is to keep their populations under reasonable control, not necessarily outright eradication. After all, they serve as a source of food for some of the beneficial wildlife in your space!
What are Aphids (what do aphids look like?)
Aphids are tiny, soft-bodied, sap-sucking insects. There are thousands of species of aphids, which can be found all across the globe. Yet aphids are most common and prolific in temperate climates such as ours. Aphids are typically pear-shaped and come in a vast array of colors. Depending on their species and food source, aphids may be grey, green, white, yellow, black, or red. Some are even furry-looking, called wooly aphids. We’ve seen all of the above in our garden!
Young nymph aphids will appear as small “dots” on your plants. As the adult aphids mature, their legs are more visible and they become increasingly mobile. Most aphid species do not have wings, though adult aphids can grow wings in crowded conditions to enhance their ability to travel to new food sources!
What plants are aphids attracted to?
Aphids will feed on a wide variety of plants, and are especially drawn to tender new growth. They can infest everything from ornamental shrubs and fruit trees to various vegetable crops. In terms of veggies, they seem favor the brassica family including kale, collard greens, broccoli, brussels sprouts, cauliflower, and cabbage. In our garden, aphids are also highly attracted to milkweed, swiss chard, carrot greens, citrus tree leaves, and leafy greens like spinach or lettuce. We don’t grow roses, but I’ve heard they can be a real problem there too.
Different species of aphids flock to different plants! For instance, we find yellow aphids on our milkweed, grey aphids on brassicas, black aphids on swiss chard and nasturtium, green aphids on our citrus and lettuce, and wooly aphids on our apple tree.
How Aphids Damage Plants
Aphids colonize on their chosen host plant, forming clusters and reproducing rapidly. As do other sap-sucking insects, aphids pierce plant leaves and stems with their mouthparts to suck sap, nutrients, and moisture from the plant. The initial damage is mostly aesthetic and localized, causing yellowing and/or curling leaves. However, a heavy population of feeding aphids can cause stress, nutrient deficiency, stunted growth, and in extreme cases, death to the infected plant. The younger the plant, the more susceptible to lasting damage it is. Some species of aphids inject a toxin into the plant as they chew, causing further leaf curl, discoloration, and growth issues.
In addition to sucking on plant tissues, aphids also emit a sticky, gooey secretion called honeydew. As aphid honeydew coats the surface of plant leaves, there is an increased risk for the development of sooty mold. Sooty mold is a general term for several types of fungus that grows on honeydew. The mold itself doesn’t technically “infect” the plants, but can inhibit photosynthesis in heavily coated leaves. Sooty mold is also considered undesirable and unsightly on prized ornamental plants, such as rose bushes.
Last but not least, the honeydew that aphids leave behind draws the attention of other insects and pests. In particular, ants love aphid honeydew. Ants aren’t all that attracted (or harmful) to garden plants themselves, so if you see a lot of ant activity on your plants, that is a very good indicator that an aphid infestation may be underway! In fact, ants love aphid honeydew so much that they actually “farm” aphids. The ants gather around, protect the aphid colony and the host plant, and even physically caress the aphids to increase honeydew production – effectively “milking” the aphids! Crazy, right?
Choosing an organic aphid control method
As you can see, aphids suck – literally! Now, let’s dive deeper into the many ways to prevent, kill or otherwise get rid of aphids. As you read through the options below, you may ask yourself – but which trick should I try? That depends on the severity of the problem, what resources you have available, and personal preference. Minor infestations can easily be managed by hand, with your garden hose, or through preventative measures. On the other hand, you may want to call in the soap or neem oil if the problem persists.
You’ll also want to consider the type of plant. For example, I personally do not love spraying neem oil directly on the edible portion of plants like leafy greens or a head of broccoli. While neem is organic and safe, it has the tendency to leave an oily residue behind that isn’t easy to wash off. Yet it works really well on the general foliage of squash plants, tomatoes, eggplant, ornamentals, and more! With time and experimentation, you’ll figure out which methods work best for you and your garden.
9 ORGANIC WAYS TO KILL OR GET RID OF APHIDS
1) Inspect Your Plants Regularly
Become a pest detective! One of the best ways to organically control aphids is to catch them early on. Then, every other method we’ll discuss today is exponentially easier and more effective. Your plants will also be more likely to rebound with little-to-no ill effects thereafter.
Make it part of your garden routine to regularly inspect your plants (e.g. weekly), which is something I suggest to manage all sorts of garden pests – not just aphids! Be sure to check the underside of leaves, and also in the centermost tender parts where new growth is. For example, I most often find aphids in the very middle of a kale plant, in a just-budding broccoli head, or other tight and protected places.
Also train your eye to recognize signs of aphid damage, before you even see the aphids themselves. Check out the photo below; I spotted the unusually crumpled section of that broccoli leaf from 10 feet away! Low and behold, aphids were clustered and feeding on the under there, out of plain sight. I smushed them right away.
2) Squish & Remove (Prune)
When you come across a small cluster of aphids, the most quick and easy way to get rid of them is to simply squish them by hand. Gently pinch, smush and wipe the leaf or stem free of aphids. I do it all the time! Now, this method may not be ideal for the squeamish, but it sure does stop them – right then and there. Because the residue from dead smashed aphid bodies is quite sticky, I usually like to hose off the area with water after the massacre.
Another easy way to quickly get rid of aphids is to cut out the infected area (when possible). If the aphid population is concentrated on just a few leaves, a small branch a tree can live without, or other non-essential section of the plant, prune it off and dispose of it away from your garden. When it comes to something like kale or tomatoes, be sure you aren’t pruning off the terminal bud – the primary growth tip that is usually in the top/middle of the plant. If you cut that away, the plant will essentially stop growing.
3) Spray Off with Water
This is another go-to method that we use to get rid of aphids, often used in conjunction with the squish method. Simply hit the aphid colony with a good hard blast of water from your garden hose! (Don’t spray so hard that it damages your plant of course.) A firm stream of water accomplishes several things: One, it physically removes the aphids from your plants. Two, the blast of water pressure may actually kill the tender soft-bodied aphids on impact. Three, the water helps remove accumulated honeydew.
4) Homemade Soap Spray (or Insecticidal Soap)
One of the few “sprays” we use in our organic garden is a basic homemade soap spray. There are also many pre-made organic insecticidal soaps available, but they include a bunch of other ingredients. Alternatively, you can make your own simple and pure DIY soap spray using just two ingredients: soap and water. Pure castile soap is the best choice for making soap spray, and it won’t harm your plants when used correctly. We use Dr. Bronner’s castile soap. This peppermint Dr. Bronner’s soap provides a further line of defense, since peppermint deters pests too!
Soap sprays work to kill aphids by disrupting their cell membrane. Essentially, it coats and penetrates their natural protective barrier, causing them to desiccate – or dry out. Insect soap spray has little-to-no residual effect. It only kills on direct contact, so be sure to spray it right on the target pests. Turn over or peel open curled-up leaves as needed to reach the aphids. Soap spray is also useful to control other soft-bodied insects like mealybugs, spider mites, white flies, psyllids, and scale. However, soap does not harm beneficial insects like ladybugs, lacewings or bees, nor is it effective against caterpillars.
To create your own homemade insect soap spray, simply combine 1 tablespoon of liquid soap per quart of water. For a larger batch, use 5 to 6 tablespoons per gallon of water. Use warm water and shake it up in your sprayer to thoroughly mix. To learn more, I highly suggest reading our article all about DIY soap spray before using it in your garden. While mild, there is some risk of sun-burning your plants if applied incorrectly or at the wrong time of day!
5) Encourage Beneficial Insects that Eat Aphids
Use bugs to fight bugs! Some insects are not desirable around our plants (I’m looking at you, aphids) while others we welcome with open arms. Ladybugs, green lacewings, and praying pantis are terrific natural predators of aphids and other small soft-bodied pest insects. With enough of them around, beneficial insects can definitely be a huge help with organic aphid control in your space.
Ladybugs in particular are ferocious predators of aphids. According to the Planet Natural Research Center, a ladybug can eat up to 50 aphids a day. That means that during its lifetime, a single ladybug is capable of consuming up to 5,000 aphids! During the early stages of their life, ladybug larvae are the most effective at controlling aphid populations. Yet ladybug larvae look significantly different than their adult form (see the photos below). Therefore, make sure you know how to recognize these good guys in the garden, and don’t mistake them for pests!
Green lacewings also readily consume aphids, though not at quite the same incredible rate that ladybugs do. An average green lacewing larvae may consume around 200 aphids (or other prey) per week.
To boost their populations, many gardeners buy and release beneficial insects. We used to release ladybugs in our garden each year, but now have a sufficient natural population that we no longer need to. If you do go this route, ensure you’re buying native American ladybugs and not invasive Asian lady beetles! Here is a trusted source for the right ladybugs, and here is a great source for green lacewings.
Tips for Releasing Ladybugs
When you release your ladybugs, here are a few tips to ensure they stick around. They have a reputation for flying off!
- When they arrive, store the ladybugs in the refrigerator until that evening. This slows down their metabolism and activity, but is totally safe.
- Release ladybugs that evening, just after the sun goes down.
- Thoroughly wet the plants that you are going to place them on first.
- Ensure you release them near a food source, e.g. aphids.
- If you order a large amount, place them in a few different locations throughout your garden.
Some may still fly away, but if you follow these tricks, plenty should stick around too! After we release ours, they may not be as concentrated in the area that we originally put them, but we definitely notice an increase in the ladybug population around our garden in general. If you can get them to stick around long enough to lay eggs and then hatch new larvae, then the feast will really begin! Also, don’t be alarmed if there are a few dead ladybugs in your purchased container. It happens.
Other ways to encourage beneficial insects in your garden is to maintain it in an organic manner, use companion planting, and practice polyculture.
6) Companion Planting & Polyculture
Growing a wide variety of plants creates biodiversity in your garden. This is a way to maintain balance, and also attract more beneficial insects. Additionally, variety and polyculture – the term for mixing many types of plants in one small space – reduces the chances of widespread devastation by pests that are all attracted to the same crop. Meaning, it may not be the best idea to plant an entire garden bed full of just broccoli and kale. That sounds like an aphid hay-day to me!
I highly suggest interplanting companion plants with your pest-prone crops. For example, tuck in aromatic plants like onions, garlic, leeks, catmint, marigolds, dill, fennel, and/or cilantro around your other garden veggies – all known to deter aphids! I have successfully kept swiss chard plants naturally aphid-free (usually aphid-magnets) by planting onions around and between the chard.
On the other hand, some companion plants can serve as a “trap crop” and attract aphids – while luring them away from your veggies! Nasturtiums are a prime example. Aphids absolutely love nasturtiums. However, be sure to periodically remove infested trap crop plants to prevent a booming population of aphids in your garden. Or, manually remove and kill the aphids from the trap crops.
For more information on companion planting combinations and natural pest deterrents, be sure to subscribe to our weekly newsletter to receive a free garden planning toolkit! There is a detailed companion planting chart included in the toolkit.
7) Neem Oil Spray
If you’ve been around the garden block, you’ve surely heard of neem oil. It is a plant-based concentrated oil, extracted from the seeds of the India-native neem tree. Neem oil is particularly effective against small soft-bodied insects like aphids, thrips, spider mites, mealybugs, scale, and white flies. The oil coats their bodies and smothers them – or otherwise interferes with reproduction and feeding. Like soap spray, neem oil will kill aphids most readily when it is sprayed directly on them.
The active ingredient in neem oil (Azadirachtin) is also a general pest insect repellent. Therefore, routinely treating plants may help prevent an aphid infestation in the first place, or stop them from readily coming back. On the other hand, neem oil is not toxic to bees when used correctly. Other beneficial insects like ladybugs, earthworms, parasitic wasps, spiders, or adult butterflies also are not negatively effected by neem – especially if they aren’t directly sprayed with it!
You can find “neem oil” sold either as concentrated 100% pure neem oil, a concentrated neem oil containing other ingredients, or pre-mixed, ready-to-use spray. Personally, we prefer to use this 100% pure organic cold-pressed neem oil and mix our own spray. It is the most cost-effective and safe. Furthermore, one pre-mixed neem oil product line was recently found to be contaminated with several nasty pesticides that weren’t included on the label, including Malathion, Chlorpyrifos, and Permethrin! Yuck.
In all, neem oil can be a great non-toxic and useful product to organically control aphids – when it is applied properly! See this detailed article for more information about how to mix and use neem oil correctly.
8) Plant Purple & Red Varieties
Did you know that pests are less attracted to red and purple vegetables? They sure are! Year after year, the purple cauliflower, purple cabbage, and red kale in our garden is significantly less damaged by aphids and cabbage worms than their green counterparts. One reasonable theory is that pests can’t blend in and hide as easily on brightly-colored purple vegetables as they can on green ones. That would make them an easy target for predators.
Furthermore, studies show that anthocyanin (the antioxidant-rich flavonoid that makes red, purple and blue-pigmented veggies so good for us!) is actually mildly toxic to some insects. It may even deter larger pests like squirrels! Therefore, try selecting and planting red and purple veggies as one way organic way to control aphids.
9) Hoops & Row Covers
One final organic aphid control method is to physically block their access to plants. Individual plants, raised beds, or sections thereof can be shrouded with row covers. Also called “floating row covers”, their purpose is to block out or otherwise protect plants from undesirable elements. Some row covers are designed to stop insects, while others are used for shade or frost protection.
I put this option last on the list intentionally. We absolutely love using hoops and row covers as a means for organic pest control in our garden. However, because aphids are so dang tiny, hoops and row covers aren’t always 100% effective at keeping those little suckers out. If you cover young plants early on, and use the right type of fine row covers with it tucked in tightly around the edges, they can certainly help. Read all about using hoops and row covers in the garden here, including details on various hoop and cover material options.
And that is how to get rid of aphids, in a natural and organic manner!
In closing, I hope this article gave you plenty of new ideas of how you can get rid of aphids in your own garden. As you can see, there are tons of effective options – and most of them are very quick and simple! Not sure where to start? Experiment with a few methods, and then come back to let me know how it goes. Thanks for tuning in, and best of luck!
Don’t miss these related articles:
- 8 Organic Ways to Get Rid of Cabbage Worms & Moths
- Over 25 Organic Ways to Stop Pests from Destroying Your Garden
- Homemade Pest Insect Soap Spray Recipe
- Learn to Identify the Top 18 Common Garden Pests + Beneficial Insects
- How to Properly Mix, Emulsify & Use Neem Oil in the Garden
- Companion Planting 101 + Free Companion Planting Chart