Over time, harmful microorganisms tend to build up over gardening soil. Consequently, this can be harmful to your crops.
If you plan to reuse your soil, it would be best to kill all the bacteria present in the soil. There are several techniques you can use to kill bacteria in garden soil, but the most common one is sterilization.
The meaning of soil sterilization
Typically, gardeners sterilize soil to free it from harmful fungi and bacteria. Commercial farmers sterilize soil before reusing it. Fortunately, soil sterilization is not as expensive as most people think.
Also, you can always sterilize your garden soil from the comfort of your own home. This soil disinfection technique is pretty much effective in preventing pests and diseases in the future.
Keep in mind that the soil you use to foster healthy seed germination should be free and clear from all pathogens. This is because seedlings are likely to pick up all bacteria from the soil and affect the overall growth of the transplant.
Even so, this does not mean that soil sterilization is not essential for growing mature plants. You still have to sterilize the soil even when growing mature plants.
Is sterilizing gardening soil safe?
At times, some people think that soil sterilization destroys beneficial microorganisms in the soil. Remember, not all bacteria are harmful to plants. So, soil sterilization can tamper adversely with soil life.
Nevertheless, you have to weigh the pros and cons of sterilizing your soil. From there, you’ll know the best method to kill bacteria in your garden soil.
The different ways of soil sterilization
At present, there are two primary techniques of sterilizing your garden soil. The first one is heat treatment, while the second is chemical treatment. Let’s look at each sterilization technique in detail.
Chemical Treatments
As the name suggests, this method involves the use of chemicals. Commercial farmers often use chemical treatments. This is because chemical treatments are relatively expensive and pose health hazards.
The benefits of using chemical treatments is that they are simple to use when dealing with a lot of soil and do not consume a lot of time and effort. Despite being beneficial for commercial farmers, chemical treatments have several drawbacks.
Disadvantages of chemical treatments
- As mentioned earlier, chemical treatments are not entirely safe for human use. They contain toxic chemicals that can affect respiratory and skin health. Ensure you wear protective garments when applying these chemicals. Protective gloves and facemasks are essential during the application process. Additionally, ensure you follow all the manufacturer’s guidelines on the chemical treatment application.
- Another disadvantage of chemical treatments is that they are usually designed to treat limited diseases and pests. You will have to use a combination of chemical treatments if you want to kill all harmful bacteria in the soil.
- It is not possible to use the soil immediately after applying chemicals. You will have to wait for the chemicals to exit the soil system before using the soil again. This delays the planting and harvesting period.
- Failure to use the correct application instructions can leave a lot of chemical residue on the soil. In turn, this adversely affects the healthy growth of plants.
- Using chemical treatments for prolonged periods can lead to resistance. Eventually, harmful microorganisms get used to the same kind of treatment; hence they become immune to these chemical treatments.
Heat Treatments
In residential gardens, heat treatments are more popular. This is because there is less soil, and it’s a safer option. Heat treatments often incorporate exposing the soil under high temperatures to kill all harmful bacteria and microorganisms.
Extreme high temperatures produce unconducive environments for bacteria, weeds, and fungal spores. Hence, they eventually die. Experts recommend exposing the soil to heat for approximately 30 minutes.
A major downside of heat treatment is that it significantly reduces the amount of beneficial microorganisms present in the soil. However, it does not wipe them out completely.
Beneficial bacteria like bacillus tend to grow in large amounts even after heat treatments. Therefore, always consider this soil sterilization method. Heat treatment is also safe since there are zero toxic chemicals involved during the process.
Nonetheless, note that heat treatments are sometimes dangerous if the temperatures are incredibly high. In such a scenario, the soil may experience phytotoxicity.
Excessively heated soil generates toxic organic compounds, soluble salts, and manganese toxicity. Thus, you have to maintain the correct temperatures required for soil sterilization.
Note that gardening soil containing organic matter is more likely to get damaged when exposed to extremely high temperatures than potting soil.
Methods to heat sterilize your soil.
If you want to give your soil heat treatment, there are several techniques you can use. Generally, there are four heat sterilization methods. They include solarization, steaming, microwave, and oven heating.
Solarization
As the name suggests, this technique involves using solar energy to kill bacteria in the garden soil. You can use solar to kill bacteria in large heaps of soil.
All you have to do is cover the soil with layers of plastic, then leave it under the sun for an extended period. Exposing the soil to high temperatures from the sun helps you kill harmful bacteria and pathogens in the soil.
Plastic is often used to trap the sun’s energy. You can always wrap the soil in small plastic bags and expose it to the sun. It would be best to use clear plastic during solarization.
The process of solarizing soil
Below are the steps of solarizing soil.
- The first thing to do when solarizing your garden soil is to prepare it. Do this by removing all dirt and debris from the soil. As you do this, disintegrate all clods and lumps. This way, you’ll make the heat treatment more effective.
- If you are solarizing potting soil, spread a plastic layer at the bottom and spread the soil on top. Ensure the soil does not touch the edges of the plastic.
- Make the soil damp by slightly moistening it. You need to wet the soil to a depth of approximately 12 inches.
- After irrigating the soil, use a plastic layer to cover the soil. Secure the bottom layer of plastic using rocks and stones. On the other hand, if you are filling plastic bags with soil, close them tightly and position them under direct sunlight. It would be best to place them in the sunnies location of your yard.
- Leave the soil for approximately four to six weeks. Even so, this time varies depending on the climatic conditions of your area. If you live in cooler areas, you may need to leave the soil under the sun for up to ten weeks.
Unlike other forms of heat treatments, solarization does not affect soil life as much. Beneficial living organisms like earthworms are likely to recolonize immediately after solarization.
Oven
Another way to kill bacteria in your garden soil is by heating the soil in an oven. This heating technique usually works well if you have small batches of soil.
Below is a detailed procedure for sterilizing soil in an oven.
- Once you finish prepping the soil, add the soil to an oven-proof container.
- Then, sprinkle it with water. Ensure that the soil becomes moist. Be careful not to overwater the soil for best results.
- Use aluminum foil to cover the container.
- Next, place the soil in an oven. Ensure you preheat the oven at temperatures of 200 degrees Fahrenheit. Then, heat the soil to temperatures of 180 degrees Fahrenheit. Leave the soil in the oven for approximately 30 minutes.
- After 30 minutes, switch off the oven and allow the soil to cool.
From this article, it is clear to see that there are many ways of killing bacteria in your garden soil. The method you choose will depend on your requirements.
How do I kill bacteria in my garden soil?
Over time, harmful microorganisms tend to build up over gardening soil. Consequently, this can be harmful to your crops. If you plan to reuse your soil, it would be best to kill all the bacteria present in the soil.
You can use several techniques to kill bacteria in garden soil, but the most common one is sterilization.
The meaning of soil sterilization
Typically, gardeners sterilize soil to free it from harmful fungi and bacteria. Commercial farmers sterilize soil before reusing it. Fortunately, soil sterilization is not as expensive as most people think.
Also, you can always sterilize your garden soil from the comfort of your own home. This soil disinfection technique is pretty much effective in preventing pests and diseases in the future.
Keep in mind that the soil you use to foster healthy seed germination should be free and clear from all pathogens. This is because seedlings are likely to pick up all bacteria from the soil and affect the overall growth of the transplant.
Even so, this does not mean that soil sterilization is not essential for growing mature plants. You still have to sterilize the soil even when growing mature plants.
Is sterilizing gardening soil safe?
At times, some people think that soil sterilization destroys beneficial microorganisms in the soil. Remember, not all bacteria are harmful to plants. So, soil sterilization can tamper adversely with soil life.
Nevertheless, you have to weigh the pros and cons of sterilizing your soil. From there, you’ll know the best method to kill bacteria in your garden soil.
The different ways of soil sterilization
At present, there are two primary techniques for sterilizing your garden soil. The first one is heat treatment, while the second is chemical treatment. Let’s look at each sterilization technique in detail.
Chemical Treatments
As the name suggests, this method involves the use of chemicals. Commercial farmers often use chemical treatments. This is because chemical treatments are relatively expensive and pose health hazards.
The benefits of using chemical treatments are that they are simple to use when dealing with a lot of soil and do not consume a lot of time and effort. Despite being beneficial for commercial farmers, chemical treatments have several drawbacks.
Disadvantages of chemical treatments
- As mentioned earlier, chemical treatments are not entirely safe for human use. They contain toxic chemicals that can affect respiratory and skin health. Ensure you wear protective garments when applying these chemicals. Protective gloves and facemasks are essential during the application process. Additionally, ensure you follow all the manufacturer’s guidelines on the chemical treatment application.
- Another disadvantage of chemical treatments is that they are usually designed to treat limited diseases and pests. You will have to use a combination of chemical treatments to kill all harmful bacteria in the soil.
- It is not possible to use the soil immediately after applying chemicals. You will have to wait for the chemicals to exit the soil system before using the soil again. This delays the planting and harvesting period.
- Failure to use the correct application instructions can leave a lot of chemical residue on the soil. In turn, this adversely affects the healthy growth of plants.
- Using chemical treatments for prolonged periods can lead to resistance. Eventually, harmful microorganisms get used to the same kind of treatment; hence they become immune to these chemical treatments.
Heat Treatments
In residential gardens, heat treatments are more popular. This is because there is less soil, and it’s a safer option. Heat treatments often incorporate exposing the soil under high temperatures to kill all harmful bacteria and microorganisms.
Extreme high temperatures produce unconducive environments for bacteria, weeds, and fungal spores. Hence, they eventually die. Experts recommend exposing the soil to heat for approximately 30 minutes.
A major downside of heat treatment is that it significantly reduces the amount of beneficial microorganisms present in the soil. However, it does not wipe them out completely.
Beneficial bacteria like bacillus tend to grow in large amounts even after heat treatments. Therefore, always consider this soil sterilization method. Heat treatment is also safe since there are zero toxic chemicals involved during the process.
Nonetheless, note that heat treatments are sometimes dangerous if the temperatures are incredibly high. In such a scenario, the soil may experience phytotoxicity.
Excessively heated soil generates toxic organic compounds, soluble salts, and manganese toxicity. Thus, you have to maintain the correct temperatures required for soil sterilization.
Note that gardening soil containing organic matter is more likely to get damaged when exposed to extremely high temperatures than potting soil.
Methods to heat sterilize your soil
If you want to give your soil heat treatment, there are several techniques you can use. Generally, there are four heat sterilization methods. They include solarization, steaming, microwave, and oven heating.
Solarization
As the name suggests, this technique involves using solar energy to kill bacteria in the garden soil. You can use solar to kill bacteria in large heaps of soil. All you have to do is cover the soil with layers of plastic, then leave it under the sun for an extended period.
Exposing the soil to high temperatures from the sun helps you kill harmful bacteria and pathogens in the soil. Plastic is often used to trap the sun’s energy.
You can always wrap the soil in small plastic bags and expose it to the sun. It would be best to use clear plastic during solarization.
The process of solarizing soil
Below are the steps of solarizing soil
- The first thing to do when solarizing your garden soil is to prepare it. Do this by removing all dirt and debris from the soil. As you do this, disintegrate all clods and lumps. This way, you’ll make the heat treatment more effective.
- If you are solarizing potting soil, spread a plastic layer at the bottom and spread the soil on top. Ensure the soil does not touch the edges of the plastic.
- Make the soil damp by slightly moistening it. You need to wet the soil to a depth of approximately 12 inches.
- After irrigating the soil, use a plastic layer to cover the soil. Secure the bottom layer of plastic using rocks and stones. On the other hand, if you are filling plastic bags with soil, close them tightly and position them under direct sunlight. It would be best to place them in the sunnies location of your yard.
- Leave the soil for approximately four to six weeks. Even so, this time varies depending on the climatic conditions of your area. If you live in cooler areas, you may need to leave the soil under the sun for up to ten weeks.
Unlike other forms of heat treatments, solarization does not affect soil life as much. Beneficial living organisms like earthworms are likely to recolonize immediately after solarization.
Oven
Another way to kill bacteria in your garden soil is by heating the soil in an oven. This heating technique usually works well if you have small batches of soil. Below is a detailed procedure for sterilizing soil in an oven.
- Once you finish prepping the soil, add the soil to an oven-proof container.
- Then, sprinkle it with water. Ensure that the soil becomes moist. Be careful not to overwater the soil for best results.
- Use aluminum foil to cover the container
- Next, place the soil in an oven. Ensure you preheat the oven at temperatures of 200 degrees Fahrenheit. Then, heat the soil to temperatures of 180 degrees Fahrenheit. Leave the soil in the oven for approximately 30 minutes.
- After 30 minutes, switch off the oven and allow the soil to cool.
Conclusion
From this article, it is clear to see that there are many ways of killing bacteria in your garden soil. The method you choose will depend on your requirements.
