How long does it take microbes to populate new topsoil?

Microbes that live in soil

Microbes are microorganisms found in the topsoils and are responsible for soil fertility. There are millions to billions of microbes in a single gram of soil- these are that are microscopic and can only be viewed under a microscope.

The time taken for microbes to populate new soil is dependant on whether you innoculate the soil or microbes to come naturally. Innoculation will greatly speed up the process to as little as two weeks, whereas the latter may take six to twelve months,

Soil fertility can be categorized into biological fertility, chemical fertility, and physical fertility. We are going to look at biological fertility in soils. The organisms living in the soil interact through a highly complex and dynamic process with the contents of the soil. The interaction is dependent on the type of microorganism, the nature of the matter, and the environmental conditions.

Microbes are of different types, including bacteria, actinomycetes, fungi, nematodes, protozoa, and algae. These microorganisms also play a significant role in the nutrient cycle, an essential factor in the ecosystem.

Soil organic matter is composed of both living and dead plant and animal residues. The living organisms in the soil are responsible for the decomposition of nonliving matter. The rate of this decomposition process depends on the nature of the organic matter and the nature of the microorganisms.

Role of microbes

Microbes are a huge part of the ecosystem, as they help in the decomposition of dead matter and help in the health of plants.

Some microbes are critical for soils fertility and the health of plants. They help break down organic matter from dead animals and plants and incorporate the same content into the soil. In the process, they improve the fertility of the soils and the structure of the soil by increasing its organic content.

The process begins with the activity of actinobacteria (bacteria with fungal-like growth habits) and fungi. These two break down the more demanding and more significant materials. Then comes other bacteria that consume and further break down the matter. This process is more vivid in a compost pile.

Mycorrhizae, for instance, is a symbiotic relationship that occurs between plant roots and specific soil fungi. These fungi grow close to the plant roots or within the cells of the plant roots. Some plants immensely benefit from this relationship. The microbes provide the plants with nutrients and defend the plant roots from attack by disease-causing microorganisms.

The decaying matter feeds microorganisms with the necessary energy and carbon for cellular growth and development. As they feed on the matter, they break it down into essential nutrients and carbon dioxide, which goes into the soil. Additionally, these microorganisms help in mineralization. This process involves the transformation of nutrients into essential minerals that plants take up through their roots.

Legumes such as clover, beans, and peas also form a symbiotic relationship with certain bacteria in the soil. This bacteria, known as rhizobia, extract nitrogen from the atmosphere, which the plants take up for their cellular functions.

The same nitrogen is transferred to animals through the food chain. Nitrogen is essential in most plants as it is used to form amino acids that form proteins. Protein is a substantial and critical part of the animal and human diet. Also, important to note is that legumes are a significant source of healthy plant proteins.

Another role of microbes in the soil is the improvement of the soil’s drainage. As the microbes move through the soil’s particles, they break them down, creating air spaces. Plant require aerated soils to thrive. It is because the plant roots also need oxygen to stay alive.

Also, microbes in the ground help in improving the drainage of the soil. Without proper drainage, water will sit on the topsoil, and air will not infiltrate through. It suffocates the plant roots causing them to die and start rotting.

Microbes, also referred to as living soil, are a significant part of the ecosystem as they play a major role in the environment. They regulate certain aspects of climate change, mitigate droughts/floods, and filtrate water through their activity.

Important to note is that dead plants and animals would not decay without these microorganisms, and the environment would have a completely different look.

Ways to increase microbes in the soil

Soil degradation is a serious problem affecting every aspect of human existence. It affects the productivity of the land and also other broader aspects such as climatic change. The key to reversing the problem lies with the activity of microbes in the ecosystem.

Companies and governments have invested huge sums of money and other resources to restoring soil fertility. This section will address some of the most effective ways of increasing microbes in the soil.

Avoiding bare land

First, we need to conserve what we already have. One of the most destructive actions to the soil and microbes is leaving the field barren. It causes soils erosion, whereby the top fertile soils are eroded by water and wind. It further lowers the fertility of the land.

Instead, bare land should be planted with crops like ryegrass, alfalfa, and oats. These crops do well even in low-quality soils. They also act as cover, preserving soils from being eroded by water and wind.

Minimize physical disturbances through controlled tilling

You can reduce the rate of tilling the land. When you turn the soil, you interfere with its structure, disrupting the activity of microbes. Microbes live in the topsoils, where they break down matter, adding to the fertility of the soil.

Tilling takes these microbes from their habitant and disrupts their activity. You should, instead, try tilling alternatives and till when it is necessary.

Growing cover crops

Growing cover crops is another effective way of conserving soil fertility. Cover crops take up carbon dioxide from the atmosphere and fix it back into the ground.

The reason behind this is that these plants are not harvested and taken away. Instead, they grow, dry, and rot on the ground. As a result, they add to the decomposing matter in the soil.

Microbes take up simple compounds in the soil, such as sugar, and transform them into micro molecules. As microbes break up organic matter, they use part of it for food creating new biomass. They then release the rest as carbon dioxide into the soil.

The speed at which they create new biomass varies depending on the amount of food and environmental factors. In other cases, when the food supply runs out, they die.

For this reason, we can boost the amount of plant carbon transformed as organic matter into the soil by supporting and enhancing soil microbes. As a result, these organisms will continually transform these dead plants and waste into soil organic matter.

We also attain healthy soils with microbes that help plants help plants fight diseases and reduce stress. Additionally, they help in the cycle of nutrients for the benefit of plants and the ecosystem.

Cover crops are a great way to increase microbial life in your soil. Check out the video below about them.

Watering your soil

Watering your garden frequently helps the microbes in the soils with their activity. It is because these are living organisms, and water is essential for their survival.

Additionally, they also require a moderate temperature level to survive. Water helps in cooling down the soil to attain the required levels. Whenever the ground dries up, the microbes in the soil also suffer from a lack of water. Besides, the temperatures are likely to rise to unbearable levels killing the microbes.


Mulching is another effective way of retaining microbes in the soils. Mulching works in a set of ways. First, it helps retain moisture levels in the soil, which is essential for the survival of microbes. When moist, the rate at which organic matter is transformed into soil nutrients useful for plants increases. As a result, you will have a healthy garden, and your plants will thrive.

The second way mulching increases the fertility of soils is because the mulch is also a form of organic matter. As it covers the soils, microbes are still working to break it down. The faster the mulching material goes down, the more fertile your soils become.

Adding compost to the garden

Compost makes a good choice of mulch. It protects against moisture loss through evaporation. It also acts as a sponge absorbing most of the water. Additionally, it provides a welcoming environment for microbes to the ground in your garden.

Using this type of mulch, make sure you water the garden generously because the compost will take up most of the water. Additionally, water is critical because the activity of microbes on the compost produces heat which might kill your plant roots.

Avoid the use of pesticides

The use of pesticides in your garden kills the harmful pests and microbes in the soil. As the pesticides are washed off the plants, they go into the ground, staying for quite some time. Over this time, they kill microbes in the soil, destroying the soil’s fertility.

Over time, as you continue using pesticides, you will realize that your garden is not as productive as it used to be. Even adding compost will not provide the expected results because it is not effectively broken down.

In summary, using these chemicals on your plant will upset the good qualities, including the soil’s drainage, aeration, and fertility. For this reason, gardeners should go for natural methods of controlling plant diseases and pests. Moreover, they should avoid using industrial fertilizers, which also kill these crucial organisms in the soil.

50% of organic matter is carbon. The ground contains more carbon than the atmosphere, plants, and animals all combined. Studies show that releasing this carbon from the soil into the atmosphere is a significant cause for the greenhouse effect, commonly known as global warming.

It is what mainly causes climatic change. However, if we can regenerate our soils, we can retain the carbon there useful and harmless.


Microbes and organic matter are found in the topsoil, making it spongy and dark. This soil is critical because it contains essential nutrients for plants, holds water and supports the microorganisms responsible for soil fertility. There is a need to conserve this top layer of the soil by inviting microbes.

The role of microbes in the ecosystem is indispensable. These organisms affect the amount of food available for human, animal, and plant consumption. Major global problems such as drought, climatic change, and global warming result from inadequate microbes in the ground.

The good news is that you can indeed control the levels of microbes in your gardens through simple methods. With all this information, I hope you can now enhance your garden’s productivity and bring forth the necessary change in the world.

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Tony O'Neill

I am Tony O'Neill, A full-time firefighter, and professional gardener. I have spent most of my life gardening. From the age of 7 until the present day at 46. My goal is to use my love and knowledge of gardening to support you and to simplify the gardening process so you are more productive

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