They may be small but tiny, little aphids can cause havoc across your borders and vegetable patches. They suck the life out of plants. So how do you get rid of aphids in the garden?
How to Identify Aphids
If you have found an insect and wonder if it is an aphid, the first thing to check is the size. Aphids are usually small, around a quarter of an inch at maximum size.
You are lucky to have spotted one or two because they can be nearly invisible to the naked eye but tend to be far easier to spot when clumped together. If you do spot one, then don’t be fooled by its colour. Aphids can come in a variety of colours including green, brown, grey, yellow and even pink.
An aphid’s body is pear-shaped, and it has two very long antennae on top of its head that sweeps back over the body. The skin can be waxy or even appear translucent in places.
Most species are wingless, although don’t be too surprised if you do see one or two with wings as this can happen when the swarm gets very large.
In Britain, aphids can vary in shape and size a little but, in general, if you find insects that fit the general description of a pear-shaped body, with antennae that are almost invisible to see because of how small they are, then you may well be dealing with an aphid problem.
So, when it comes to aphids, you’re looking for:
- Pear-shaped black, grey, green, yellow or brown body
- Tiny bodies up to a quarter of an inch
- 2 long antennae that go back over the body
- Waxy and/or translucent skin
- No wings in most cases
It is actually fairly unlikely you will notice any aphids until they are causing a problem. You are more likely to identify an aphid problem because of the symptoms your plants are suffering from rather than finding the aphids themselves!
What Damage Do Aphids Do?
The damage a swarm of aphids can do is fairly intense, and this is the most likely way you are going to identify the problem. Yes, when it’s probably too late.
The first sign of a problem will be that your plants just aren’t thriving as they should be. You might notice that previously healthy plants have started to yellow or the leaves have started to curl.
This is because the aphids multiply and swarm all over your plants, and each one feeds on the plants’ juices. These juices are what contain the nutrients your plants need to survive and thrive. The aphids don’t mind which part of the plant they attach to so you can find them swarming over the leaves, stems, buds, flowers and even fruit of the plant.
Aphids do tend to prefer newer growth, so watch out for young plants, especially.
Another sign that aphids have been in your garden is a sticky substance that can coat the plants’ leaves and stems. This is actually the sap of the plant that is left behind when the aphid has finished feeding. If enough aphids are in your garden, this can leave a noticeable residue.
You may also find that if the aphid infestation has been left to grow, plants may suffer from a mouldy growth, making the plants look blackened.
Those are some of the signs of the damage, but what does this damage do long term?
Well, it can cause the plants to lose too much nutrition and, therefore, die. But it can also cause disease and virus transfer between other plants. The plants’ flowers or fruits can end up deformed, and in some cases, you won’t be able to nurse the plant back to health.
Although small, they are one of the most damaging pests you have to deal with in the garden and why you must get rid of aphids.
How to Get Rid of Aphids
Aphids can be tricky to find, and they can wreak havoc in your garden, but they can be dealt with using a variety of methods, many of which are natural and shouldn’t cause any further harm to your plants.
All methods work best if you catch the problem early, so keep an eye out for signs when working in your garden.
Use Cold Water
Aphids might be deadly to your plants, but they aren’t the most quick-witted of insects. If they fall off the plant they were feeding on, they are unlikely to find their way back to the plant. Spraying cold water on the leaves may well be enough to do this.
This works best if you only have a minimal infestation to deal with. So if you are lucky enough to spot aphids early then, this method might be all you need. Spray the aphids then take a look the next day and spray again until you no longer see any signs of the aphids.
Be careful not to use a spray that’s too powerful because you run the risk of actually spraying aphids from one plant to another and spreading their destruction around the garden.
Make Your Own Insecticide
If spraying the infestation with water doesn’t work or you have a larger infestation to worry about then you can make your own insecticides and sprays.
Grab yourself a spray bottle and fill it with water and a couple of teaspoons of liquid dish soap. Give the mixture a shake to mix it up and then spray it directly onto the infected leaves and stems.
Pay special attention to leaves’ undersides because this is where the aphids are most likely to be hiding.
You are likely to need to keep doing this for several weeks. So, every two to three days head outside with your homemade spray and spray the plants. In a few weeks, you should notice a big difference.
You should keep doing this until your aphid problem has disappeared entirely. If you stop early then, you may find that the infestation comes back.
Add Diatomaceous Earth to Plants
Not everyone has heard of diatomaceous earth, but this is an amazing powder made from crushed sea life fossils. If you buy food-grade level, then you can be sure it won’t be dangerous to you or your plants.
It might not be bad for you, but it is deadly to aphids – great news if you have an infestation and want to finally get rid of aphids who are taking over!
To use diatomaceous earth, make sure you wear a mask first. This is a very fine powder, and you don’t want to be breathing it in. Simply, sprinkle it over your plants, and it will kill the aphids for you.
This does work, but it may not be your best option because it is also harmful to other insects. It is particularly harmful to bees, and you don’t want to discourage bees from your garden, and no one wants to kill these helpful insects.
Avoid this method in the height of summer when bees and other bugs are at their most busy in your garden.
Try a Systemic Pesticide
You may need to invest in a systemic pesticide for challenging infestations that have grown large and out of control.
These are a type of pesticide that you spray or apply directly to the plant, and it is absorbed into the tissues of the plant. You can buy these from your local garden centre. Just be careful to buy one that is suitable for aphids and check the instructions carefully.
You need to ensure it is safe to use on the plants you intend to use it on.
Also be warned that the majority will not be suitable for edible plants (for example, if you have an infestation on your tomato plants). Always read the label carefully on any pesticides before using them to get rid of aphids.
If you follow the instructions on these pesticides, you should get rid of your aphid problem within a few weeks.
Deploy Biological Controls
This sounds far scarier than it really is. What this actually requires is introducing predators to aphids into your garden. There is a range of online stores that will sell ladybugs, Asian beetles, and more to then introduce to your garden to work their way through eating up all the aphids.
In the UK, you can purchase your biological controls from Defenders. In the US, try TipTopBioControl for purchasing natural predators.
This is one of the best ways to get rid of aphids in your garden naturally.
How to Prevent Aphids
As is often the case with dealing with many pests when gardening, preventing aphids from getting hold of your garden is better than trying to cure the problem. After all, if you haven’t got aphids in the first place, then you don’t need to worry about how to get rid of aphids.
Encourage Beneficial Bugs
There are a few insects that absolutely love to make aphids their favourite meal. If you encourage these bugs into your garden, then you are unlikely ever to have too much of an aphid problem in your garden.
The bugs that really like to eat aphids are ladybugs, lacewings and some types of wasps. You can encourage these types of bugs into your garden by creating an environment they will love.
These are pretty bugs that won’t harm your garden, and they can do a lot of good. You can encourage them into your garden by planting plants with big, flat blooms and a high pollen count. Try plants such as cosmos, yarrow and angelica.
You can also provide them with places to hide, especially in winter. Create sheltered spots using bark or bundles of bamboo. The insects will love this and make your garden their home.
Apply Dormant Oil to Fruit Trees
During the winter, your fruit trees go into a type of hibernation and enter a dormant state. When the buds start to grow is the time to apply dormant oil.
You can purchase these from garden centres, and they are oil-based sprays that you spray onto the buds of the trees. They provide a protective coating that suffocates any nesting insects and their eggs.
This can mean you enter the high growth part of the gardening season with a protected garden that is less likely to attract aphids and other nasty insects that may harm your plants.
Add Plants That Aphids Dislike
Aphids might be destructive but, like any creature, they have their likes and dislikes. They won’t like plants with strong aromas and tastes such as garlic, chive oregano, sage and even leeks.
If you add a few of these plants to your garden, then they may put off the aphids from coming into your garden at all.
How NOT to Get Rid of Aphids
We’ve covered a range of options for both getting rid of aphids but also preventing aphids in the first place. However, there are a few things you should avoid using when getting rid of them.
At Pests Banned, we always encourage using (and only using) natural preventative methods for getting rid of any pests. The same applies to aphids.
Of course, chemicals are likely to work to get of aphids but they will also seep into the ground killing off beneficial insects. This can then run off into nearby waterways killing aquatic life.
At all costs, please avoid using chemicals to deter aphids – no matter how annoying the infestation is!
Traditional moth balls are actually banned across the EU. This should tell you all you need to know about why using them is not a good idea.
They contain naphthalene or paradichlorobenzene, both of which are a risk to human health. The fumes alone can be toxic. Do you really want to use something with such high toxicity in the garden?
Ultimately, don’t use anything in the garden that can cause yourself, your children, your pets or other wildlife harm. Yes, aphids are a nuisance. Yes, it can be frustrating. But that doesn’t mean you should resort to the use of dangerous, toxic chemicals.
To sum up, if you have an infestation, whether it’s a big or small problem, there is a solution you can try to get rid of aphids.
You may find that you need to use a few methods before finding the one that works for your garden.
Your best option for preventing them and, therefore, not need to get rid of aphids in the first place is to keep a good eye on your garden and spot the signs of aphid damage early.
Use the methods outlined in this article to get rid of them before they become a big problem.
Ryan is a keen gardener from the UK who’s spent years dealing with countless, common pests over the years so knows the ins and outs of how to deal with pests in the garden