How to make potassium soap: the best organic insecticide and fungicide

how to make potassium soap at home.

To provide the best possible care for your plants, it is important that you are aware of how to make potassium soap. Because it turns out that this is an excellent organic insecticide and fungicide.

Its use is quite common in gardening and horticulture, and the best thing is that we can make it at home. Let's get to know it a little better and examine the steps that need to be taken to do it.

Potassium soap as an insecticide and fungicide for your plants

Potassium soap as one of the best pesticides.

This soap is created through a chemical reaction between potash and fatty acids. Giving rise to a product that is soluble in water and that It has important insecticidal and fungicidal effects, because it weakens the protective layer or waxy cuticle that covers both insects and fungi.

It is a good ally to avoid infections, but also to eliminate pests or diseases if these have already occurred.

When it comes to insects, potassium soap is effective against all those that They have a soft body, like aphids, aphids, whiteflies and thrips. When soap comes into contact with these insects, it penetrates their body and causes damage that affects their ability to feed and reproduce.

In the case of fungi, it is particularly effective against powdery mildew and mold. If you apply it to the leaves, it can be of great help in eliminating fungal infections.

Potassium soap It is always applied diluted in warm water and sprayed over the entire plant., especially in areas that are affected by pests or diseases. It is advisable to apply first thing in the morning or last thing in the day so that the direct impact of the sun's rays on the soap layer does not cause damage to the plant.

Regarding the frequency of application, it is recommended to use it every seven or 10 days, especially if there is a persistent infestation. If used preventively, it can be applied every three to four weeks.

In comparison with other insecticides and antifungal treatments, potassium soap is considered a safer option for the environment, because its contaminating potential is lower. Besides, It is less harmful to those insects that are beneficial and we do want them close to our plants, like bees and butterflies.

In any case, although potassium soap is a safe option as an insecticide and antifungal, we must keep in mind that not all plants have the same level of resistance. That's why it's better Start by applying a small amount of the solution to a specific area and wait a few days to check if there are any adverse reactions. If this does not occur, we can apply the product with complete peace of mind.

When making homemade potassium soap, the result is always different, so we recommend doing this test every time you are going to use a new soap.

How to make potassium soap step by step

how to make potassium soap step by step.

Potash is a chemical product, and it is advisable that you always handle it with caution, protecting your eyes and hands. To be possible, Also use a mask to minimize the risk of inhaling gases.

To make potassium soap you need:

  • 150 grams of caustic potash (potassium hydroxide).
  • 300 grams of vegetable oil (you can use used olive oil).
  • 1,5 liters of distilled water.
  • A heat resistant container.
  • Whisk.
  • Thermometer.
  • Gloves, protective glasses and mask.
  • Soap mold.

Measurement and preparation

The amounts we have given you are approximate. The proper ratio is 1:2:10. That is, one part caustic potash to two parts vegetable oil and 10 parts distilled water.

Once you have protected your face and hands, carefully pour the potash into the water. Do not do it the other way around, because when you add water to the caustic potash Hazardous splashes may occur. Stir well until the potash dissolves.

In a heat-safe container, Heat the oil to about 50º or 60º degrees. Without letting it come to a boil. Slowly add the potash and water mixture to the oil, stirring constantly. You will see that the mixture begins to thicken and emulsify quickly.

Blend and check consistency

Continue whisking constantly until saponification occurs, which is the point at which the chemical reaction that produces soap occurs. Keep mixing until you see that the mixture acquires a consistency similar to that of thick applesauce. This process may take some time, so don't be impatient and keep stirring the ingredients.

Saponification test

Its goal is to make sure that the chemical reaction has actually occurred. For it, Take a small sample of the mixture and put it in water. If a kind of milky solution forms, you have done it right.

If it doesn't work, continue stirring for a while longer to integrate the components well.

Cool and store

Cool and store your potassium soap.

When it comes to how to make potassium soap, it is important to exercise caution throughout the process and not be in a rush. Once saponification has occurred, let the mixture cool slightly. Afterwards, you can pour it into the mold.

Now is the time to allow the soap to harden completely, for which we must wait for it to cool completely. Then we can unmold it, but We still need a little more time to start using it.

If you used a block mold, you can cut the soap into smaller pieces. But, in any case, Allow it to dry (cure) for a few weeks in a cool, dry place. before you start using it.

Did you know how to make potassium soap? You have verified that it is not complicated at all, but that it is advisable to take extreme precautions because potash is a chemical product that can cause significant burns. If you protect yourself well and work carefully, you will create a soap that will be very useful for domestic cleaning, to do the laundry, and also to take care of your plants. Do you dare to try it?

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