How to Get Rid of Aphids Naturally: Identification, Prevention & Control
Whilst not as damaging as some other pests, aphids can be a real nuisance to your plants. These tiny creatures can form large colonies on the underside of younger leaves, shoot tips, and flower buds, and the damage that they cause can have a real impact on plant health. But aphids are also a key part of the ecosystem, and they are a vital source of food for many garden visitors. So how bad are aphids really, and what can we do to reduce their numbers in our gardens?
What are Aphids?
Aphids are tiny, soft-bodied insects around 1-7mm in length that suck the sap from any tender parts of a plant. This produces a sticky biproduct known as ‘honeydew’ that can cause black sooty mould to grow on your plants if left untreated. Ants love this sweet substance and will actively farm aphids, protecting them from natural predators to maintain their food supply. While greenfly and blackfly are the most common types of aphids, there are actually over 500 different species in the UK.
What Damage do Aphids Cause?
Small infestations of aphids shouldn’t cause you many issues, with natural predators normally managing a small infestation. However, large colonies can impact your plants. Aphids won’t outright kill them, but the damage they cause can lead to your plants perishing, so you need to keep an eye on any developing colonies. Because aphids drain the plants of sap, this can cause stunted growth as well as curled or distorted leaves. This then weakens the plant and if it is young, can be fatal. Aphids can also transmit viruses between plants that can cause some major issues.
This all sounds very dramatic, but don’t worry – there are various options to help control their numbers and keep your plants safe.
What are the natural predators of aphids?
Your best defence against aphids is to encourage their natural predators into your garden. Ladybirds, hoverflies, lacewings, and various birds are just some of the creatures in your garden that enjoy feasting on aphids. A lot of these predators are also excellent pollinators, so grow plenty of bright, colourful, pollinator-friendly flowers to encourage them into your garden. Setting up a birdbath, especially in the hot summer months, can be a great way of attracting more birds to your garden.
Generally, it’s best to tolerate aphids as much as possible to allow the ecosystem in your garden to thrive.
How can Companion Planting Help With Aphids?
Another very natural way of helping manage your aphid population is to use companion planting. By planting certain plants that aphids find attractive, you will steer them away from your precious crops and flowers. Sacrificial planting can also act as a lure, as many plants that aphids enjoy are attractive to pollinators, many of which happen to be their natural predators. Read more about companion planting in our helpful blog here.
How Do I Deal With Aphids?
If you want to actively do something about aphid infestations, especially indoors where natural predators don’t exist, then squashing them between your fingers is a popular method of control. This can be all that’s needed to deal with a small infestation, and whilst it can be a bit sticky, it’s a very simple way to protect your plants. You can also dislodge aphids with jets of water, but be careful not to damage your plant in the process.
Many people will advocate for various types of sprays from organic to homemade to chemical-based. Some of these are very effective at killing aphids whilst others have mixed results, but it’s important to note that this method of pest control can have a detrimental impact on other wildlife in your garden. Not only can it enter the food chain this way, but the larvae of various predatory insects are also killed by products that target aphids. This then reduces the amount of creatures that can naturally deal with your problem while also drastically impacting biodiversity.
Using worm castings can be a great way of helping your plants grow stronger whilst specifically targeting aphids. This is because the castings contain an enzyme called chitinase that breaks down exoskeletons and kills aphids when ingested.
If you place some worm castings around the base of your plant, it will absorb all the beneficial nutrients to help it grow stronger and healthier as well as the chitinase. As the aphids suck the plant’s sap, they ingest the enzyme and meet their demise. You can also make a worm casting tea to spray on the plant’s leaves that will do the same thing. Because chitinase targets exoskeletons, this can also help with other pests like mites.
