Solutions to eliminate aphids from your plants

Published Apr 9, 2022 

The aphid is perhaps the most frequent pest in gardening with the permission of mites, mealybugs and whiteflies. This insect can be green, yellow, black or red; there are many different species. Surely you have already seen it in the tender shoots of some of your beloved plants. If not, you should meet him because without a doubt sooner or later you will see him.

With complete certainty, this pest is the one I have had to deal with the most in the years that I have been a gardener. When the cold is over and the plants begin to wake up, the aphid joins the feast of the tender shoots even if nobody invites it. From spring to autumn you should check the growing areas of your plants and the underside of the leaves to detect them in time.

The aphid colony will multiply at high speed, the sooner you discover the plague, the easier it will be to eliminate it. Throughout this article I will try to provide you with some solutions.

Personally, in the last season these small insects have done great damage to the plants in my garden. The most attacked by aphids were Kales, but they also attacked broccoli, lettuce, tomatoes, string beans, etc. That is why I want to talk to you about how to prevent and eliminate this pest.

1. Aphid characteristics

Even if you are not a fan of biology, I encourage you to learn something about these little bugs. If you know enough about them, you can identify them and learn how to prevent them.

Aphids are small insects, just a few millimeters long, but easy to see with the naked eye. They belong to the order Hemiptera like mealybugs and whiteflies, which you may be familiar with. Like these, they feed on plant juices. Their biting and sucking mouthparts are used to pierce the plant and suck its sap.

Aphids have a preference for the most tender parts of the plant, forming a large group of individuals in which adults and nymphs coexist. In the advanced stages of the plague, they can completely cover the growing areas.

The plague appears with good weather and almost explosively. The reproductive characteristics of the aphid mean that, in a short period of time, the number of individuals goes from a few to hundreds or thousands of them on a single plant.

2. How to prevent the aphid

Provide your plants with optimal care so that they do not have deficiencies. A weak plant is more susceptible to pests and diseases.

Avoid fertilizing with too much nitrogen. The excess of this element causes plants to grow excessively, favoring stems that are too tender... a delicacy for aphids and other parasites.

Keep the garden or pots free of weeds. In addition to giving a bad image, they will be a fantastic refuge for the aphid.

Plant rosemary, lavender, mint and other aromatics near the plants most susceptible to this pest. The aroma of some aromatics repels harmful insects.

Encourages the existence of useful insects that feed on the aphid such as ladybugs, lacewings, hoverflies and parasitoid wasps, for example by avoiding broad-spectrum insecticides.

3. How to eliminate the aphid

If despite your efforts the plague establishes itself in any of your plants, it is not a drama either. This parasite is one of the easiest to remove. Now I tell you how to do it.
Assess the degree of affectation. If the attack is not severe or is found early, manual removal of aphids or light pruning of invaded areas may be sufficient. The hose can also be a great ally. Something as simple as repeatedly spraying the damaged areas with pressurized water can help you kill the aphid without the need for chemicals.

3.1 Potassium soap

If this is impossible for you due to the number of affected plants, you can apply a treatment with potassium soap. You dilute this product to 2% in water (or what is the same, 20 ml. of soap for every liter of water) and spray it on the affected areas, you will see that you immediately notice improvement. Despite this, you must treat again after 2 weeks to ensure the elimination of the aphid. I advise you to make at least 3 applications, respecting these time limits. Don't forget to spray the back of the leaves well.

3.2 Neem oil

Another ecological and environmentally friendly alternative is Neem oil, which serves both as a repellent and as a contact insecticide. It has a certain systemic effect thanks to its active ingredient: azadirachtin. It combats the aphid but also other pests such as the red spider, the white fly or the cochineal; and all this without harming other beneficial insects.

If neither potassium soap nor Neem oil have been sufficiently effective separately, think that you always have the possibility of combining them -without risk, of course, for your plants-. Potassium soap will act as a wetting agent in this case, enhancing the qualities of Neem oil. Just pay attention to handling the dosages marked by the manufacturer and apply them safely.

As a last option you can use useful insects for crops. Both ladybugs, hoverflies or lacewings will kill a large part of the plague. There are also some parasitic wasps that introduce their egg inside the aphid and, in the style of “Alien, the eighth passenger”, when the larva hatches, it devours it from the inside.

More information:


Organic Solutions for Aphids.

Biological Control of Aphids