Aphids are little annoying creatures that feed on your favourite plants, ruin your crops and reproduce faster than you can say “What happened to my onions?”.
So what do you do to save your plants from these countless predators? Continue reading to learn all about aphids and how to control them.
What Are Aphids?
Before we jump in all the prevention methods and extermination techniques, let’s learn more about aphids.
What do Aphids Look like?
Aphids are nasty little insects that have a pear-shaped soft body and love to suck plant juices. If you have a garden, you probably have aphids.
They come in many colours - grey, black, white, brown, red, orange, golden and green. They don’t have wings but will grow them when attacked so that they can leave the colony and search for new plants. Their size varies from 1 to 7mm.
Those include the woolly aphids on apples and the woolly beech aphid. Speaking of, there are more than 4,000 species of aphids and all of them live in colonies and feed in clusters.
Where do aphids live?
You can often find woolly aphids on plants, under curled leaves, hiding from predators. Most species spend the winters as eggs and wait or spring to hatch but if the climate is warmer, they can be a constant problem.
Aphids can create multiple generations in just under a year so they can become a real problem for the people dealing with the infestation. Which is why it’s so important to know the signs and treat them early, so you can save your garden.
Aphids not only feed on the plants but they also carry many viruses that can spread and ruin your crops especially potatoes, grains and citrus.
Also see: How to Identify, Prevent & Control Potato Bugs to keep you potatoes safe from this pest.
What do Aphids eat?
Their favorite food is branches, buds, fruits and soft stems, overall tender parts, not the hard already established foliage. This is because aphids pierce the stems, and they can’t do it if it’s already grown and though.
Most of them don’t mind the type of plant they will be feeding on which is why they can be found almost anywhere.
Aphids produce a sweet substance called “honeydew”. With it, they attract ants that become their natural protectors from other predators.
So if you follow an ant trail in your garden, you are very likely to find an aphid cluster. Ants even herd aphids into small colonies so that they can collect the honeydew afterwards.
So how does an aphid infestation look like? Let’s see...
What Does Aphid Damage Look Like?
Both the adults and nymphs feed on the juice of flowers, fruit, roots, leaves and stem so you have to look everywhere when checking for signs.
Here are the most common indications of an aphid infestation.
- Sap trails - They are formed when aphids feed on trees and their honeydew falls on whatever is under the tree, forming a trail.
As we mentioned, ants love it so you can often find them feeding on the substance.
- Deformed foliage - The leaves that have fallen victims of aphids will appear yellow, stunted, curled, and overall misshapen.
If you notice leaves like that, look under them to see if there are any insects there.
- Deformed fruits and flowers - They are also not exempt from aphid damage - deformation and distortion are very likely to happen during an infestation.
- Sooty mould - This is a mould that grows on the sap trails from the honeydew that has fallen on your windows, outdoor furniture, car, etc.
The fungus will grow on the sticky deposits and turn them black. It’s very easy to spot, which is why it’s often one of the first signs people notice.
- Galls - These are unusual growths that are induced by aphids and other insects. During their feeding, aphids release special growth-regulating chemicals that affect the tissue of the plant.
Causing it to form a gall. You can find them on roots as well as leaves.
How To Get Rid Of Aphids
Physically Removing the Aphids
This technique might seem like a little too much on the nose, but it is definitely the cheapest method out there. This method is especially useful if the aphid infestation is localized to only a single plant or a part of the plant.
Remember to put garden gloves on and go carefully through all the leaves, stems, flower buds, fruits, etc. This is the best option for your plant’s health. Fill a bucket with cold soapy water and drop the little insects inside.
You can also cut the damaged areas and drop them in the bucket. We realize that this may not be as advantageous if the population of aphids and the area affected is large.
Using Soap and Water
Soap and water is quite simple, cheap and environmentally friendly. Not only that, it takes very little time and produces excellent results.
Make your own pesticide by mixing water and liquid soap in a small bucket. Use a plain soap, not one with extra moisturizing or degreasing properties.
Spray this solution on the affected areas and re-apply it every 3 days for about 2 weeks. Make sure that it’s evenly applied, especially under the leaves, where most of the colonies hide.
This technique causes minimal damage to the plant itself but washes the waxy coat off the aphids leaving them vulnerable to dehydration and eventually death.
It only affects aphids and other soft-bodied insects, so you don’t have to worry about beneficial ones like bees, ladybugs and lacewings. It is important to ensure that the soapy water is not too concentrated because then it could damage the plants.
Another version of this mixture includes cayenne pepper. Stir together 1 tablespoon of liquid dish soap and a pinch of cayenne pepper into a small bucket of lukewarm water and spray the plants where they are most affected.
Spraying Aphids with Cold Water
Blast them away with cold water and they won’t be able to go back to the same plant. You can use your garden hose for this, but be careful with the more delicate plants that you have so you don’t damage them along with the aphids.
If you are on in the market for a reliable hose, you'll find our best garden hose reviews quite informative. This technique is known to work mostly at the beginning of an infestation, while there are still not that many of the pests.
Dusting All Plants with Flour
For large infestations, we recommend that you dust all the plants with flour as it constipates the pests and will quickly make them go away.
Using Neem oil and Horticultural oils
Neem oil and horticultural oils are very effective in the battle against aphids. They suffocate the insects and disrupt their membranes. However, don´t apply them if it's too hot since they can burn and injure the plants.
Letting Predatory Insects Loose
Another way to kill aphids naturally is to raise the population levels of some predatory insects in your garden. Plant fruits and flowers naturally attracting such insects, and you can reap benefits. You can buy many of these insects online for very reasonable prices.
Once you let them loose in the soil, these predatory insects will consume the aphids rapidly and eventually as the aphid population goes down, the predatory insects will die off on their own or move on.
The insects best known for having a special appreciation for aphids are the Lady Bug.
Applying Diatomaceous Earth
Another option is diatomaceous earth. It's an organic material made from tiny abrasive seashells and other fossils that penetrate the insects and kills them instantly.
Don't apply it when your plants and flowers are in bloom since it's harmful to the beneficial insects, as well, like pollinators. It works on all kinds of pest infestations.
How To Prevent Aphids
Spraying Dormant Horticultural Oil
Kill the aphid eggs settled on your shade and fruit trees, by spraying dormant horticultural oil on them. This is a type of oil that is used to control pests during the off-season - late autumn, winter and early spring.
The only thing you have to do is mix the oil with water and pour the mixture into a spray bottle. Make sure to follow the directions on the packaging.
Apply the pest solution to the trunk of the tree, the leaves (make sure you don’t miss their bottom parts), stems, and branches.
Check the instructions to see when you have to re-apply the treatment.
Attract Aphid Eating Insects
Many insects would gladly eat the aphids such as ladybugs, parasitic wasps and lacewings. You can order supplemental populations of those insects online.
If you don’t want to order them online, you can put some nectar-producing flowers such as alyssum, hyssop and cilantro close to aphid-susceptible plants.
The flowers will attract the insects close to the aphids and they will be eaten right away.
Plant Aphid Repelling Plants
Just as some flowers can attract beneficial insects, there are also those that can repel aphids. Place the repelling plants around the crops you want to protect.
Repelling plants include onions, leeks, garlic, catnip, sage, leeks, oregano. Most of them you can even use in your kitchen, so it’s a win-win situation!
Divert Aphids Away from Your Plants
Another thing you can do is plant some attractive weeds far away from your green babies so that the aphids won’t be tempted to go there.
These include mustard, sowthistle, nasturtium, and calendula.
Wrapping Up How to Identify Aphids and Control Them
Aphids can be very stubborn and hard to get rid of species since they reproduce so fast! During the summer and late spring, female aphids give birth to live nymph, skipping the whole egg stage.
Those nymphs need about a week to have offspring of their own and about now you can imagine that they don’t need a lot of time to fully infest your garden and become trouble.
Which is why we recommend that you take immediate action at the first signs you see. When trying some of the DIY methods, make sure to always read the instructions of the products you are using and wear protective gear when working with chemicals.
And if you think things have gotten out of hand, don’t hesitate to call a professional for consultation and expert treatment. It will surely save you a lot of time and save your garden and crops from severe aphids damage.