Uses of Potassium Soap in the Orchard or Garden

Uses of Potassium Soap in the Orchard or Garden

Potassium soap has always been used as a natural stain remover. But today we are talking about another of its uses, that of a homemade insecticide to prevent the most common pests in the garden or orchard in an ecological and natural way.

What is potassium soap?

Potassium soap is not toxic, it is an ideal insecticide for naturally fighting pests, especially aphids.

Composition of potassium soap.

Potassium soap is made up of three main elements: water, vegetable oil and potassium hydroxide (potash or caustic potash).

When vegetable oil comes into contact with potassium hydroxide, a chemical reaction occurs, resulting in water-soluble glycerin. A mixture with an alkaline PH does not affect plant tissues.

Uses of Potassium Soap.

Potassium soap is mainly used to fight against aphids, it will act by direct contact, it touches the aphids, it damages their skeleton and the aphid dies. This without affecting other larger insects such as bees.

Potassium soap, in addition to putting an end to the plague, sanitizes the plant, so that, for example, ants no longer come to eat the typical remains (molasses) left by aphids on plants or fruit trees. This will keep our plants healthier.

It has a fungicidal effect.

It is biodegradable, once it detaches from the plant or tree and falls on the earth, it becomes potassium carbonate, the earth itself will assimilate it and become one more component, enriching the earth .

It is not harmful or toxic to pets or humans.

When to use it.

It can be used at any time, although it is advisable to apply it at sunrise or sunset. Do not apply it in direct sunlight, it could burn the leaves. You have to be careful not to apply it on a rainy or windy day, you will lose some of its properties.


The recommendation for the maximum dose of potassium soap is 20 grams per liter of water. Although it will always depend on our particular situation.

In this sense, we must be careful and experiment first with small doses.


The application system will be by spraying, about 3 or 4 times, leaving a few days of rest between treatment and treatment.

How to make homemade potassium soap.

I recommend this express recipe to make potassium soap quickly and at home.


Or buy.

You can find potassium soap for cleaning, for example, at Mercadona, where it is sold as a mild natural soap that removes stains, under the Beltrán brand. The price is quite affordable and it will last you a long time with the recommended doses.

You can also use “lizard soap” in the bars, but keep in mind that the soap is made from vegetable oils.

You can also find it online at Amazon, of course.

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