Methods of sanitizing potting soil: Sometimes, after repotting our plant, we see it suffers from fungal diseases and regrets changing the soil. If you do not use suitable and safe soil for your pot, you will have such problems. There is a possibility of fungal diseases and harmful bacteria in the soil composition, so always disinfect them before using different soils. In the following, we explain different non-chemical methods to sterilize potting soil; stay with us.
Suitable soil for planting seeds and plants
If the pot’s soil in which you plant your plants has disease or insect eggs, it will gradually decrease your plants’ growth and even can cause their death. Heating the soil is one way to disinfect and use it safely; this method is also called pasteurizing. By this method, you will eliminate the pests; just heat the soil to 170 F ( 80 degrees Celsius ) for 30 minutes, and after that, you can use this soil.
Benefits of sanitizing potting soil
If you continuously use the same soil for your pot, the soil will contain pathogenic bacteria, viruses, insects and fungi, so this is enough to increase various diseases in your plants. In such a situation, sanitizing potting soil can be a good way to decrease diseases and improve the soil’s quality. Another benefit of soil disinfection is weed seed elimination. Most people who are engaged in the production of seedlings tend to use sterilized soil. Disinfecting the soil is useful when you want to reuse the potting soil. Be sure to read the article Mold on Soil of Houseplants.
How To Sterilize Soil?
I recommend you don’t trust the soil you buy from outside and flower shops (with all due respect to the sellers). Do the disinfection at home; there are easy and convenient ways you can disinfect your pots and plants, that you can easily do at home, which we will discuss in the following:
How To Sterilize Soil by oven?
Before doing any work, set the oven temperature to 170 F ( 80 degrees Celsius ) so that it heats up, and then pour the soil into baking paper and cover it with aluminum foil. Put it in the oven for 30 minutes; just remember to shake the soil every 10 minutes so the heat reaches all parts. When you heat the soil, its microorganisms will be lost, so in order to increase the soil’s beneficial microorganisms, put it in a dark place for two months. This procedure may cause a bad smell, so if you are very sensitive, do it outside the house. If you want to do it outside the home, you can put the soil in a pot and put it in a temperature of 80 degrees Celsius for 20 minutes and shake it every 10 minutes as above so that the heat reaches all the soil.
Using the bag and steam method to sterilize potting soil
Another method of disinfecting the potting soil is using the bag and steam method; you should fill the warm bag with soil mixture and then add a glass of water inside the bag. Mix it with the soil so that the soil becomes moistened. Now put the bag on a pan and then make 2 or 3 holes in the bag. These holes cause steam to go out of the bag and reduce the pressure inside the bag. Note that the water temperature should not be higher than 170 F ( 80 degrees Celsius ); otherwise, soil’s useful substances will turn into harmful substances. If you don’t have access to a bag, you can use a container that only steams out, and the time is about 30 minutes.
Sterilize the potting soil with boiling water
It is enough to fill the pots with soil before use and pour boiled water (212 F or 100 degrees Celsius) on the soil until the water comes out from the bottom of the pot. This method destroys any non-useful organisms in your pot’s soil, and you have easily sterilized the soil.
Use of chemicals to sterilize potting mixx
Soil parasitic fungi such as Phytophthora, Pythium, Phoma, Fusarium, Armillaria, Roselina, and several other soil fungi can cause root rot, seed rot, seedling death, wilting, and drying in different soil conditions in terms of temperature and humidity. Many of these plant parasitic fungi can be controlled by using one of the fungicides in the form of directly mixing the poison with the soil or using it in irrigation water.
When you use fungicides and bactericides, you should ensure they are safe for the target plant. Research has proven that metalaxyl + Zineb fungicide effectively controls rot caused by different species of Pythium fungus in geranium. Prothiocarb fungi can also be used to control various types of Pythium.
Other things you need to know
In begonia, the fungicide Previcur in the amount of 0.15% and Fosaaloxyl in the amount of 0.05%, as well as the mixture of Mancozeb + Metalaxyl in the amount of 0.75%, when used in water, had the best results in controlling rot caused by the fungus Phytophthora cryptogea. In cloves, to prevent vascular wilt caused by Fusarium fungus, Prochlorase fungicide at the rate of 2 grams per square meter of soil And at the time of transferring rooted clove cuttings and repeating it every ten days will have a very favorable result.
Homemade method to sterilize potting mix
If you don’t have access to the mentioned chemical materials described in the previous section and can’t fulfill the above conditions, you can disinfect your pot soil by adding one teaspoon of charcoal and one teaspoon of tea dregs. Pay attention the tea must be dehydrated, otherwise the wet tea residue will damage the pot.
The process of repotting and sanitizing potting soil
If you are confident that the soil you buy is not disinfected; just do the following two irrigation with fungicide after using this soil when reppoting or planting seeds so that fungal disease won’t be transferred to your plant.
Summary of sterilizing pot soil
This article explains the methods you can use to disinfect your pots’ soil at home. The first point you should observe is to buy soil from a reputable brand or store. One of the common methods to disinfect your soil is to heat it to sterilize it. The following method is to use soil disinfectants to destroy any diseases. This article has been reviewed by Tibor Janda.