Having the right microbes in your soil is important to your plants. They can stimulate root growth and increase nutrient absorption. They can also help plants resist stress.
Healthy microbial populations provide a system of checks and balances that can suppress disease organisms, insects and nematodes. They are primary decomposers and improve nutrient availability.
Adding Organic Matter
We are often told that we need to improve soil health, but what is not well understood is the crucial role microorganisms play in this process. They are responsible for nutrient cycling, organic matter production, ecosystem primary production and more. They are also the driving force in determining soil structure, water-holding capacity and the ability of plants to absorb nutrients.
Beneficial soil organisms produce hormones that promote root growth, break down organic compounds into soluble forms and enhance the availability of minerals to plants. They convert nitrogen gasses in the soil into a form that can be absorbed by plants, and they break down other organic substances like dead plant material and manures.
In addition, microorganisms increase the soil’s cation exchange capacity or CEC, which helps to hold and release important nutrients such as calcium, potassium and magnesium. They also make the mineral forms of phosphorus and nitrogen more soluble, which makes them more available to plants.
Adding organic matter is one of the best ways to encourage beneficial microorganisms in living soil. This is because it provides a food source for them. When the microorganisms in the soil have a good food source, they are more active and their activities improve.
Another way to encourage microorganisms in living soil is to keep it well watered. This is because microorganisms thrive in moderate temperatures and moist conditions. In dry conditions, the microorganisms die. It is also a good idea to avoid physical disturbance of the soil such as tilling.
While tilling is not ideal, it is better than leaving the land completely bare. Tilling crushes aggregates which breaks down the carbon they contain and gives microorganisms access to the underlying soil. It is also recommended to mulch your beds with organic materials such as leaves and pine needles. Besides preserving moisture and adding organic matter, mulching also reduces the need for chemical fertilizers. This is because microorganisms will be able to produce their own natural fertilizers from the organic materials in your soil. The microorganisms will then pass these nutrients on to your plant roots.
Adding Organic Fertilizer
One tablespoon of soil contains about 50 billion microorganisms. These tiny organisms are like mini nutrient-manufacturing machines, helping transform living soil into a healthy and fertile environment that can provide plants with essential nutrients. Beneficial bacteria are a critical part of this process, performing a wide range of functions, from enabling nitrogen uptake to killing off fungus gnat larvae.
The microbes in the soil also work with roots to help them absorb nutrients and break them down into usable forms. They can also produce hormones that encourage plant root growth, improve nutrient uptake and even fight off harmful pathogens and insects.
A healthy microbial population in the soil can help it retain water, improve aggregation, prevent soil erosion and reduce the need for chemical fertilizers. It can also lower the amount of fungicide and antibiotics needed to treat diseased plants, and it can make it easier for grasses and fruit trees to absorb nutrients from the soil.
Many organic farmers use natural fertilizers to encourage the growth of these helpful microorganisms in the soil. These products may include compost, humus or other types of organic matter that are beneficial to the microbes. They might also incorporate kelp, which provides the microbes with a high-energy food source.
If the soil is not being fed, the number of microbes in the soil will begin to decrease. This can happen when the soil is overworked, or if it’s too dry and hot. It can also happen if the soil is regularly treated with chemical fertilizers, which kill microorganisms and disrupt the microbial community.
To increase the numbers of beneficial microorganisms in the soil, it is often recommended to add a commercial product containing these organisms, or even a homemade organic tea made from organic materials. These bio-fertilizers can increase the microbial populations in the soil by more than 300%, and they will continue to thrive as they feed on organic matter and other organic material. The microbial communities in the soil can also be encouraged by incorporating cover crops into the garden or yard. These plants will act as a habitat for the microbes, and they will also provide food for them through their roots.
Adding Compost
The main food source for microorganisms in living soil is organic matter such as compost and natural mulches. Soil microorganisms will increase or decline based on the amount of available food. The microorganism population in the soil will eventually equalize over time based on what the climate and soil can provide.
Soil microorganisms are very important to soil health and plant growth. They help break down organic matter into more easily absorbed compounds that are used by plants. They also make up the humus in the soil, which helps retain moisture and provides a reserve of nutrients. They create symbiotic relationships with roots (rhizobia and mycorrhizal fungi) and promote nutrient availability and mineralization. They also produce plant hormones that can improve plant vigor and reduce disease.
Many people think it makes sense to “increase” the numbers of beneficial microorganisms in their soil by applying a commercial product containing specific microorganisms or making homemade “organic tea.” In reality, most commercial products and organic “teas” have minimal impact on the number and activity of existing soil microorganisms. Some of these products may actually harm the existing microorganisms by introducing pathogens or other undesirable organisms.
In fact, the best way to increase the number of beneficial microorganisms in the soil is to add organic matter, like compost or well-made organic fertilizers, to the soil. This will provide the microorganisms with a steady supply of food and help them stay healthy.
In addition to providing food for the microorganisms, the organic matter will improve the structure of the soil by allowing the hyphae of the fungi and actinomycetes to better aggregate the soil. This will help the soil hold water and nutrients, while reducing erosion. Organic matter is also important in preventing droughts by slowing the loss of water to the atmosphere.
Adding a Mulch
In addition to nutrient cycling, microorganisms perform a number of other beneficial functions in the soil including: promoting root growth, breaking down nutrient forms into more readily available ones, suppressing pathogenic organisms, and releasing hormones that can help plants respond to stress. Microorganisms also play an important role in aerating the soil, which helps to improve water retention and facilitate nutrient absorption.
The health of your garden depends on a balanced microbe population, which stops their growth and encourages the development of lateral roots. If too few of these helpful critters are present, your fruit trees may not thrive. But nurturing your soil’s microbial community doesn’t have to be difficult or time consuming. Here are a few ways you can encourage and feed these vital little critters:
Mulching conserves moisture and introduces organic material into the soil. It also acts as a physical barrier that inhibits the germination of weed seeds. This reduces the need for chemical weed control and makes it easier for the microbes to access the nutrients that they need to thrive.
When choosing a mulch, look for one that is made from organic material such as leaves, pine needles, or composted manures. These materials will slowly decompose and enrich the native soil as they do so. In addition to conserving moisture and introducing organic material, living mulches keep soil nutrients from being washed away in rainstorms.
In general, mulches should be kept relatively loose and not piled up against tree trunks or plant stems as this could interfere with the microbes’ ability to move through the soil. A layer of mulch about two inches thick is ideal.
Avoid tilling your beds as this disturbs the microorganisms that live in the soil and can cause them to die off. Tilling also interferes with aeration, which is essential for good soil health. If you must till, do so gently or lightly to avoid damaging the delicate structure of the soil.
There are a number of commercial products on the market that contain free-living soil microbes. Some of these contain microbes that fix nitrogen, while others include fungi that release hormones that promote root growth and suppress disease-causing organisms. Some of these products also contain phosphatus-solubilizing bacteria that help make nutrients more readily available to your plants.
