How to turn your waste into high-value compost that can regenerate soil

Written by Wesley Soule, certified soil microbial consultant

Defining what is good compost?

When people think of compost there can be many different images that pop into their minds; dark and dry material wet sloppy and very stinky, soft and crumbly or even just piles of woodchips mixed with manure. So, what is it?

Good compost is created by mixing the right ratio of organic materials to allow a diverse range of microorganisms to decompose the material creating hummus and an ecosystem of aerobic microbes.

That is what good compost is in nutshell. We turn organic waste materials into soil-building hummus and use the microorganisms to provide similar benefits to our soils. Bacteria, Fungi, Protozoa, Nematodes and Macro-arthropods like Earthworms are the organisms we aim to cultivate when making compost. This is the less spoken-about side of composting, the microorganism that takes on the role of creating healthy soils and forming symbiotic relationships with plants. If we compost correctly, we can cultivate a set of microorganisms which bring a range of benefits to plants and soil, however, if we cultivate the wrong set of microorganisms, we can see adverse effects on plants. This is why misconceptions about the quality of compost exist. NOT ALL COMPOST IS CREATED EQUALLY. Without understanding the role of microorganisms in fertile soil, we cannot see the value in creating compost which is rich in microbial numbers. So, what do these microorganisms do in healthy soil? This is to do with the Soil Food Web which is our way of understanding the soil ecosyste

Benefits of using compost rich in Microorganisms

All these benefits come from the functioning food web of microorganisms. The interconnected nature of the ecosystem requires all the microorganisms to be present in high enough quantities to support healthy plants. The graphic below gives you an idea of the different organisms which are required to make the system work. This is work done by Dr Elaine Ingham who first described this relationship between plants and soil microbes in detail.

Image 1: An example of what a good healthy microbial active compost should look like
Image 2: The picture above illustrates the soil food web

The above chart shows how energy is transferred from the sun, through photosynthesis and released by the plant back into the soil. The root exudates give energy to the soil and support the whole microbial community which provides a range of benefits to your plants. When we compost, we are looking to develop a full set of the microorganisms you see above so that they can be used to regenerate the soil. By using a recipe and combining organic waste materials we can develop the correct community of beneficial organisms. Fungi, bacteria, protozoa and nematodes are groups with millions of different species each with specialised functions.

What can the Soil Food Web do for my plants?

Reducing Pesticide Needs
Many pests that modern agriculture faces today result from poor soil microbial life. Fusarium, root aphids, fungus gnats or root-knot nematodes are but a few examples of these common pests that plague the farmer. By developing a healthy soil microbiome there is a diversity of many organisms and conditions that limit and inhibit these pests. Other pests found on the foliage can also be controlled with a liquid application of these biocontrol organisms which are both selective for pests and organic. Healthy soils are rich in Aerobic microorganisms which are better adapted for that environment than some disease-causing organisms which we find in low oxygen or anaerobic soils. Creating the right microbiome within your soil means less pest pressure. By eliminating the sources of these pests through natural biocontrol methods you will not only save money but also valuable yield lost previously to pests.

Reduced Herbicide Needs
Many of the species we call weeds are pioneer plants that have short lives where seeds are produced as quickly as possible. In natural systems, these plants are found in disturbed soils where rapid ground cover is needed. The longer the soils are undisturbed the fewer weeds you see as other plants begin to take over. The process at work in the soil is the development of soil fungi which can begin to spread out due to the lack of disturbance. The result of higher fungal levels is increased levels of ammonium and a decrease in nitrite levels. This shift causes the weeds to be less successful and the need for herbicides decreases. This is an Ecological process we call Succession and is it as much about the development of the above-ground plants as well as the below-ground microorganisms. Taking it a step further through testing your soils the microbiome can be tailored to the needs of your crop so that your microbes provide the best balance of nutrients for the needs of that specific crop

Reduced Fertilizers Needs
The activity of a healthy Soil Microbiome turns organic materials, sands, silts, clays and rock fragments into plant-available forms. The Bacteria and Fungi mine these resources with powerful enzymes and concentrate the nutrients in their bodies. Once a predator consumes and releases these nutrients back into the soil now in a form perfect for plants to use. This process occurs in concentration around the root zone of plants as the plant is feeding the microbes through the process of Root Exudation. This process provides all the nutrients needed by a plant if the microbial numbers are high enough which often is not the case in farmed soils. The soils need to rejuvenate with biologically rich inoculations before the nutrient cycling process can match the need of the plants. These minerals are found naturally in your soils and can be unlocked by using a healthy soil microbiome. In practical terms, we are reducing the number of fertilizers annually and increasing profit margins.

Capture Atmospheric Nitrogen
Through the use of specific cover cropping and bacterial inoculations, you can withdraw from the vast pool of Nitrogen in our atmosphere. Using what we call Nitrogen fixation you can utilise a free and unlimited source of atmospheric Nitrogen. The relationship between certain plants and nitrogen-fixing bacteria known as rhizobacteria which capture free forms of Nitrogen out of the air. It is then stored in nodules found on the root systems of these plants where it can be accessed. The beauty of composting is that rhizobacteria are found abundantly in the manure of ruminant livestock and are recycled through the composting process. The resulting compost can be used to inoculate crops with rhizobacteria to harness the benefit of these organisms’ Nitrogen capturing ability. With the current price of Nitrogen, there is no cheaper source than this and it is produced in the soils right there for your plants as was intended.

Reduce Erosion of Topsoil
Better water infiltration of soil prevents even heavy rains from eroding the soil, the microorganisms create the soil structure needed for increased infiltration. Bacteria start by creating small, aggregated clumps of soil which start to form the pore spaces for water to travel through. Glomalin is a glue-like substance created by healthy fungi in your soil that glues the small bacterial aggregates into larger aggregates. This process creates structures that allow water or air deep into the soils. These long passageways are vital to allow water to pass through the soil rather than run off the top. Healthy soil microbes create soils that can infiltrate water at a much higher rate. This means your soils are holding the water rather than letting it wash the topsoils away. By holding the water like a sponge, the farm will have greater access to water once the dry season begins. Not only do you prevent erosion on your land, but you hold that water for your crops for when they need it most.

Deeper Roots
The activity of good microorganisms creates soil structure by building both soil aggregates and pore spaces. The role of each organism is slightly different. The fungi or bacteria produce glues to bind themselves onto soil matter to form aggregates. Our nematodes and protozoa will move these aggregates while in search of food and by this activity we create a more stable soil structure that allows both deeper air and water infiltration. The earthworm works the soil like a natural plough creating large pathways and inoculating the soil with more beneficial microbes. All of these organisms do the work of preparing the soil for your plants allowing the roots to reach deeper and deeper every year we leave it untilled. The deeper the roots go the greater their surface area for nutrient and water acquisition which results in greater yields.

Capture and Sequestration of Carbon
The Soils of this planet are a sink for over 2500BnT of carbon where they are stored for many years if undisturbed. Once these soils are disturbed the carbon is released as CO2 which is a greenhouse gas. Having an agricultural system that limits disturbances will allow carbon to be stored in your soils as plants capture CO2 and Fungi hold it in their structures. Through good soil management, you can sequester up to 10 Tons per hectare per year which slows the effect of climate change. Many countries are talking about the power of Caron Credits to help farmers earn income from their good farming practices. While it is difficult to see that happening now it will become increasingly important as we face the climate crisis. Taking the steps today to begin storing carbon and reducing the risks we face from climate disasters may be the best way to ensure stable weather for our future.

The benefits of turning waste into compost

This is a two-fold solution of diverting a waste stream to create a beneficial product that can be sold or used to improve soil quality on your land. This is a sustainable solution for long-term reductions in expenses for crop production as the waste stream now creates highly valuable compost which can supplement your plant’s needs. Turning carbon and organic matter that was waste into microbially rich compost you can develop the natural processes in the soil again to offer the wide range of benefits mentioned above. This results in your operation being more profitable and by focusing on the quality of compost you can begin to see changes in your crops from only one application. Once you have access to a Compost Turner you can scale up the composting process even offering services to deal with organic waste from other sources in the area which is a potential revenue stream in itself.
Wood waste, animal manure, abator waste and green waste can be costly expenses to deal with, especially in large quantities. Having the operating procedures to deal with this waste is different for every operation but the guidelines for effective composting remain the same. By looking at your waste streams as material to create compost which can either be sold or used on your land it becomes clear that this is a simple solution. The benefits of what microbially rich compost can provide are outlined in a later section but in essence, you harness the power of microorganisms to bring fertility to your soil. This can work on a farm of any scale and is shown to be one of the most cost-effective ways to produce food in comparison to the rising cost of Conventional Agriculture. By putting natural soil-building organisms back into your land the soil will be able to supplement your crop for years to come. Through understanding the role of microorganisms in the soil we can see that harnessing their potential is the future of farming. Keeping the farmer profitable, growing consistent yields and returning fertility to the soil is what sustainable farming should mean. By composting and using microorganisms we can achieve this.

This guide will go through the different factors that produce good compost and teach you the principles of how to repeatedly get results. By following this recipe, you can achieve repeatable success and produce compost which offers real soil-building potential. As we go through the composting sections that offer details about composting, I would like to stress that you consult that before just learning the recipe. Compost as a product is largely misunderstood as there have been no standards or regulations set for its microbial value which is where the real value of compost lies. The products currently sold as compost are not what this book refers to as good compost. This speaks to the need to understand the role of the microorganisms we are cultivating in this process which is why reading through the first sections is vital to your understanding of compost.

What happens in thermophilic composting

This process uses the enzymes and heat generated by active microorganisms to decompose organic matter. Heat is generated from the rapidly multiplying microbes; with the right conditions a bacterium can replicate every 10-20 minutes. This population explosion will quickly heat up and decompose the available organic matter in the pile. If done right this can leave you with a well-broken-down and microbial-dense compost to make use of.

Using the right composting process, we can make use of specialised microbes to break down organic matter into compost that is rich in organic carbon and microorganisms. Through heat, enzymes and replication these microbes will turn large volumes of organic material into a valuable bio-stimulating and soil-building amendment. Compost can be used as a solid form to cover the soil, or it can provide material to extract microbial life to put back onto the land. A composting system allows you to turn organic waste into beneficial agricultural inputs for your crops at very low costs.

Humans have been composting waste materials for many thousands of years. Simply creating a pile of organic matter large enough will encourage decomposition which is likely how it began. We have come a long way since then, but the fundamentals are the same. Allowing the microbiology to decompose organic matter into smaller and smaller pieces until it forms a compost with high levels of humus, diverse microbial life and active nutrient cycling.

However, this process is limited by time. The old style of a pile which is just added to when waste material is ready will take a great deal of time, sometimes years before it yields good quality compost. By understanding the needs of the microbes doing the decomposition improvements have been made to the way we compost. Through testing a recipe and procedure have been created to not only speed the process up but improve the resulting compost. Here are some important things to provide for your microbes.

Image 3: An onion farmer in South Africa turning old waste into valuable compost using maize rests, onions and small amount of cow manure. This is a win-win situation since there are no more stinking waste lying around on the farm attracting pests etc.

Critical factors to make good compost

By understanding these key factors, the process of good composting becomes more intuitive. These requirements are basic for any healthy ecosystem to function and that is really what we need to view this compost as, an ecosystem. By setting these factors consistently to the right values we can achieve good compost and high rates of decomposition.

  • Oxygen: The type of microbes we want to promote are known as Aerobic microbes, meaning they need an oxygen-rich environment to thrive. These microbes are beneficial to your plants as opposed to the microbes that prefer low-oxygen environments which can be harmful. We want to give the best chance for the beneficial microbes to dominate the space so we must make sure the oxygen does not drop below 6 ppm. This parameter is managed by the design of the compost system, the moisture levels and the recipe we use. We do NOT want this pile to start to go into the low-oxygen zone because this is when we start to see the pathogenic organisms start to succeed. To keep a compost pile aerated enough we need to look into the turning process and how to manage this compost.
  • Water: Along with lots of oxygen we need to provide some water for the microbes to live off, water is life after all. Oxygen and water are a balancing act adding too much water cause the microbes to drown but not enough water cause them to dry out. To get the right moisture level the material should be wetted to 60% moisture content before mixing anything. This means that the whole compost pile has enough to support the microbial community. If the pile becomes overly wet the oxygen levels will decrease to a point where the beneficial microbes die out. Managing moisture is the same as managing oxygen, the two are linked.
  • Temperature: The microbial community can thrive in most ambient temperatures but when creating compost pile temperatures can rise drastically. The best way to explain this process is by imagining a dance club that is filled with people all dancing and moving around. They generate heat from doing this and the room becomes very warm. Imagine this on a microscopic level, all the microbes are eating and reproducing rapidly causing a large temperature rise. The problem can be that if the pile isn’t cooled down the microbes will cook themselves causing a die-off. monitoring temperature means we prevent this by turning the pile before this happens. We want to keep the hot centre from overheating and killing the good microbes, we do this by turning the pile and separating the contents of the hot centre to the outside of the pile while the material that was on the outside is now brought into the new hot centre. This is a vital step in our process.
  • Food sources: This is an aspect related to proper recipes. By balancing the ratio of ingredients, we can give the right number of foods to the specific organisms that we are looking to develop. Skewing the ratio is either Carbon heavy or Nitrogen heavy will lead to different results but will cause a sub-optimal compost. If the ratios are very off, then the compost won’t heat up enough or it won’t stop heating up. You can breed pathogenic microbes which can use human or plant health issues. Sticking to the right ratio of ingredients will prevent issues from arising.
  • Time: The maturation phase of the compost pile is where we see the quality improvement and the completion of the soil food web. The process of compost maturing focuses on the development of the microbial community. After the food sources of High Nitrogen and green material are consumed there is an abundance of carbon and bacteria which remain. These food sources allow for fungal communities and bacterial predator populations to rise to balance the remaining food. The completion of the process is where we see fungal predators and nematodes that feed on other nematodes. It is this full expression of the Soil Food Web that we are looking for to achieve compost that is Bio-complete and will initiate all the beneficial soil improvements we are after. Most composts are not given time to mature as the aim is just to reduce waste and sell it off. By developing the compost, we enhance its benefits and can charge more due to this increased potential for soil building.
Image 4 (Above) :An example of a 2 week old compost pile made up of wood chips, cow manure and straw in the central part of Mozambique


When making a pile there are a few things to understand before following a recipe and the main aspect is Carbon to Nitrogen ratios (C: N). Everything has a C: N ratio and this is a metric that helps us know how something will decompose. Here are two examples that show the difference.

  • Material like woodchips have a high-Carbon value and therefore will decompose slowly, require mostly fungal enzymes and won’t decompose without a composting cycle. Chips can be stored before use.
  • Material like manure has a very high Nitrogen value and therefore will decompose quickly, mostly bacterial food with some fungal interactions. This will decompose quickly losing its Nitrogen value as a gas which can often be smelt as ammonia. When you detect this smell in composting you are effectively off-gassing potential nitrogen which could be supplementing a plant’s Nitrogen needs. These materials cannot be stored before use without losing Nitrogen.

These two examples show how we need to treat materials differently based on their C: N numbers. One easy way to understand this is that Carbon is the brake of the car while Nitrogen is the accelerator. Carbon will slow the decomposition of Nitrogen while Nitrogen will speed the decomposition of Carbon. So that is why we balance the C: N ratio with the aim of getting a 30:1 C: N ratio. This is where the recipe that we are making comes from, a balanced C: N with materials laid out into 3 different parts which are all mixed evenly and kept at a consistent moisture level.

The recipe is 6-3-1 Carbon – Greens – Nitrogen by volume of the pile. Below there is a list of common items which the composter can deal with. Balance these items according to the ratio above and you have the right balance of materials. Remember your Carbon material can be stored so it is best to have a reserve of it on standby for when you have some High Nitrogen collected. When using high-carbon material like wood chip remember to keep the size of the material down to pieces of 5 cm to ensure easy turning and enough surface area needed for decomposition.

Image 5: The picture above shows the distinctive colour when a compost windrow is turned for the second time (dark one at the top)

C: N of the Ingredient

Table 1: The table above gives you an idea about the ratio of different organic materials which are suitable for composting

Tailoring your recipe to the environment and starting materials that you have available is part of the process to consistent results. Making small adjustments based on the state of your materials is reasonable. For example, a stable might be swept out with a stable waste mix of manure and hay/sawdust. This is suitable for composting but the ratios of C: N is different in this material, so we need to adjust our recipes because that’s the material we want to compost. Another common example is using older manure that is dried out. Some of the nitrogen value has off-gassed and the manure has a higher carbon value, therefore we may mix more of this manure into the pile as there is less nitrogen in that manure component now.

Image 6: Doing the third and final turn after adding all the ingredients layer for layer, turning after each layer is added to ensure proper mixing


We are wanting to make rows of material so that we can maintain a set size for the pile across the entire volume of material. By keeping the row size constant, we allow for the timing of the turning to be the same for the whole compost pile down the length of the row. The size should not be wider than 3 meters or higher than 1.6 meters so that the compost turner can turn the material evenly. The importance of keeping the pile the same size is also related to the need to turn the hot centre when ready. We want to keep the hot centre from overheating and killing the good microbes, we do this by turning the pile and allowing oxygen to cool the pile.

Another key aspect is the moisture content. We need to be sure to make all the starting material a good 60% moisture before the first mix. This will mean the moisture is evening spread throughout the pile and you won’t have dry spots where decomposition doesn’t happen. Mainly this will mean we need to soak some of the woody carbon material to get them started. When turning the pile expect that some moisture has been lost, remember to wet the pile while using the turner to get the moisture levels back to 60%.

Image 7: This image shows how the compost row should look and what is actually happening inside


The first step is to select a spot where we can begin to create the piles. Flat, open land is suitable, but we need to make the soil underneath the pile slightly compact to allow us to work on it. Driving heavy machinery over it or adding some extra lime can harden it up enough.

We then begin by collecting the material in the ratios mentioned. These materials should be mixed equally to form. As mentioned above we must be sure that our material is 60% moist which can be determined by a squeeze test. This is especially important for the carbon woody material; the manure should be wet enough if it is fresh. If you are using older woodchips or dry carbon sources you will need to pre-soak these in water for a couple of days before mixing the pile, this leads to better results as the carbon breaks down more evenly.

Then we mix the piles and make sure the size is even across the pile. When mixing try to ensure the contents of the pile are mixed evenly so that there is a good distribution of all the components of the pile. Keeping to your 6-3-1 Carbon – Greens – Nitrogen ratio will help to have this equal distribution. Note that this recipe works on volume rather than weight so follow this based on pile sizing. High Nitrogen materials like manure need special attention when mixing as they will often clump together. Things like cow manure that has dried slightly will not mix well unless broken up in the mixing process, you want to make the pile equally mixed with these materials. Once you have mixed the pile fully and are confident that the moisture levels are right give it a day before returning to check the temperature.

If there is a lot of rain or very warm days ahead, it may be best to cover the pile with some tarps or other material to prevent it from drying out or flooding. Consider building a small open shed with just a roof to cover from rainfall and sun drying. Moisture is critical to the decomposition rate of the compost, be aware of is drying out from wind and sunlight which will slow the process down. Temperatures that are too cold will also slow the process down significantly be aware that in the cold season you may need to increase the Nitrogen content of the pile to generate more heat. If heavy rain is predicted the pile will need to be covered as all the excess moisture will lower the oxygen levels. This can cause the incorrect microbial community to gain dominance of the pile and negatively affect the quality of the compost in terms of plant response.

We watch the temps and when they reach a certain level, we begin to turn the pile. We do want to avoid the pile overheating and cooking all the good microbes, so the temperature needs to be checked often. Try to check at once to twice a day to be sure the pile is heating up correctly. You will likely need to do three turns 3 times until it is ready. Once the pile does not reach the same high temperatures as before we can see the Nitrogen has been used and we have begun the maturing phase. Temperatures should hit a plateau during this phase as it slowly cools down the ambient temperatures. The size of the pile should also be decreasing with time as the microbes break the organic matter down into smaller and smaller pieces.

Knowing when to turn

Turning is one of the most important steps to composting organic waste effectively. As we have already talked about, heat, oxygen and temperature we know the importance of looking at these metrics. However, when looking to timing your turn to the right point we focus directly on the temperature. Temperature is the best way to know when to turn because we can use it as an indicator of microbial activity with the temperature reaches a certain level within a predetermined time, we know the activity of the microbes is at the desired level. This can be like a runaway train if not turned at the right time with the microbes cooking themselves out which will cause a die-off. As the microbial numbers are spiking, they are also consuming much more oxygen so if not dealt with the increased population will change away from the good aerobic organisms we are after. This reduces diversity and changes our microbial community to only selective organisms that can tolerate high temperatures and lower oxygen. So, the process of turning brings the temperature down by introducing more oxygen and redistributing the microbes. A good turning of the compost will slow down the process of composting and shift the food sources around the pile. This results in a decrease in temperature and the reintroduction of high Oxygen levels slowing down the process. This means that turning is a critical aspect of good composting and understanding when to turn needs to be carefully considered.

Image 8: Knowing when to turn your compost is extremely important. When it is time to turn you need to do it quickly and efficiently.

Temps guide

Before looking at the critical temperatures that require turning let us look at the physical structure of the pile. The most intense heat generated is at the centre of the pile as the least cooling from the environment occurs along with the lowest oxygen diffusion. This part of the pile is essential to the success of the composting process as this is where temperatures are reaching the ranges we are looking for. These high temps are decomposing faster than the rest of the pile along with destroying potential weed seeds which can be a vital aspect when composting some materials. When composting consider that each part of the pile must spend enough time in the centre of the pile to achieve proper decomposition, especially in the first days of the thermophilic cycle. That is why we generally look at a 3-turn process giving each third of the pile equal time in the hot centre. So, when we test the temperature of the pile, we must be doing so in the hot centre which means a long probe thermometer. SoilScopes offers compost thermometers that meet the requirements and give accurate digital readings. Below you will find a guide to turning your compost. These temperatures are taken from the centre of the pile at a number of locations before turning. Remember ambient temperature effect this pile too so consider the seasonal aspect of composting along with the location of where you are on your land.

These are guidelines set by Dr Elaine Ingham and the Soil Food Web school who have extensively tested this process. The results we are aiming for are high microbial diversity so following the recommended ranges will help consistency. Many things will cause slight differences in results so by keeping temperature and turning times as constant as possible we can achieve more reliable results.

Table 2: This table above shows when is the correct time to turn your compost pile

How long does the process need

After we have done the thermophilic cycle, we need to allow the microbial community time to develop. This is the maturation phase, and it can run between 2-6 months. If you have composted correctly and temperatures were in range, then you can feel confident to use it sooner. Understanding the quality of your compost is discussed in further detail in the next section.

In biological terms during the thermophilic cycle, we created a large population of bacteria as they consume the Nitrogen and store the nutrients in the bodies. By the time the turning cycle is complete the majority of the Nitrogen has been stored in the bodies of the bacteria which allows the Protozoa to begin feeding on them. This is a vital part of the development of the compost to begin offering more soil-building properties when applied. Now that the pile is stable with lower temperatures no turning is needed and the fungal community has a chance to begin decomposing the carbon-heavy materials. This is a far slower process due to the stronger bonds and specialised enzymes required to decompose these woody materials. While this process takes place, we will begin to see fungal predators such as Nematodes begin to have access to a food source along with the nematodes’ predatory species. This ecosystem in its complete form offers the wide range of benefits mentioned above. Without completing the biological cycles that these groups offer we cannot expect to reap the full reward of Biologically Complete compost.
A visual cue to seeing a well-matured pile is that there is a thriving community of macro-arthropods that inhabit the compost piles. Red worms, pot worms, Isopods, millipedes or Spring Tails are some of the very common decomposers which are easy to spot in the compost. They are important parts of the system and are broken up into two groups.

Shredders – They will chew on organic matter and break it into smaller pieces to speed up decomposition. The increase in the surface area of the organic matter allows for more microbial activity and decomposition of that material.

Microbial feeders – They crush organic matter to extract the microbial nutrition from the material. This material is then broken up and has increased surface area to speed up decomposition. Most commonly the role of the worm in the system these Microbial feeders are also inoculating the soil with their gut inoculation which is comprised of a range of highly beneficial species of microorganisms.

Having a pile mature to the point where these organisms are in abundance means you can be confident that your material is well on the way to becoming a mature compost which will offer the best soil building potential. Having this as an inoculation means you can extract these organisms to inoculate large areas of land and bring about soil sustainable soil regeneration.

Testing the quality of my compost

There is a wide range of tests that can be conducted on the compost but learning to use one’s senses is the best way. Smell, colour, texture and other simple tests exist so that you can compare the quality to a benchmark for the result we are aiming for. However, because the starting material can vary so much, we want to look for signs things could have gone wrong.

  • Strong odours – If the pile smells of putrid waste or ammonia then we have gone anaerobic. These strong organic acids are produced by anaerobic organisms and will decompose material, but it lacks the potential for improving soil health. If you begin to smell acidic or vinegary smells, then the process is beginning to shift to lower oxygen levels and should be turned. A good smell is earthy, sweet and likened to a forest floor.
  • Colour – This is a visual test that is similar to telling the difference between dark chocolate and milk chocolate. We are aiming for a nice hazelnut brown colour of milk chocolate, with slight variations of this on the starting material. We do not want to see a dark chocolate black colour which indicates high temperatures. This is a common misconception of what most compost is sold as, very black and dried. If we see this burned compost the leading cause was an incorrect recipe which was very heavy Nitrogen. The heavy use of manure or other high Nitrogen sources causes extreme temperatures which essentially burns the material to a charred black colour. This style of composting looks more to reducing waste rather than producing compost that will provide soil-building benefits. The blackened compost can still be used but should be reinoculated by processing through worms or other means. To reduce the chance of burning your compost lower the Nitrogen component of the pile or do more turns before allowing it to rest.
  • Moisture – If the pile has dried down significantly to below 30% or become soggy in the rain this can affect the quality of the microbial community negatively. Maintaining constant moisture levels throughout the entire process is a key factor to good decomposition rates and developing a functioning soil food web.
  • Texture – If your material has become very clumpy or compacted this can indicate issues in the process and quality. The aim is to have light and fluffy material that has many airpath ways. There should be some aggregated material but nothing sticky. Some people like to sift their compost into different grades but if you have composted well there should be no need for this. A mature compost may still have some harder wood chips that remain, but it should be packed full of microorganisms, especially fungi. These are completely fine to include in your compost and have many additional benefits in building Soil Carbon levels.

These are all tools that give insight into what the microbial community may look like, but more accurate tests exist. SoilScopes provides microbial Biomass Assessments to determine the quantities of a range of organisms that inhabit the compost. Working out the weights of each of these organism groups allows us to know which crops this compost or soil will have the best results on. Having determined the numbers for your microbial groups means the compost can be assessed for its quality to see if the process is working well. Having a test done allows the results to be compared to a database to see which areas of the process can be refined or if all the numbers are high it can be used to regenerate soils. A Microbial Biomass Assessment is the best way to understand the value of your compost along with determining the efficacy of your composting process.

Image 9: A picture of a PTO shear bolt replacement on a WN3000 Compost Turner in the Western Cape, South Africa

Application guide

Usage of solid compost
Once we have completed the composting process and allowed for maturation there is now a large quantity of microorganism inoculation ready to be used on your land. The compost can be used as a solid soil amendment to place over your garden or land. This works well for potted plants and in raised beds where the compost can be used as the major component of what plants are grown in. The benefits of making good compost will be evident at this point and seeing healthy plants will be your reward for the process. Once we look to larger scales compost applications become very difficult as the volume of well-made compost does not scale up very well. However, by understanding that the value of this compost lies in its microorganisms we can make extractions of those microorganisms into a liquid form. Once in a liquid form, we have access to a powerful soil inoculation where a little goes a long way if treated correctly. Looking at the size of most Agricultural fields the need to use liquid extractions of microbially rich compost becomes clear.

Making a liquid extraction

This process has many details like composting but to put it simply; Compost is used as an inoculation source and placed in a meshed bag. The bag is placed in a bucket filled with water. It is then agitated enough to remove the microorganisms from the compost material and get them floating in the water. This solution must be used immediately or aerated to sustain the microbes before they die off. Once they are applied to the soil they will begin to replicate and begin the process of building a functioning soil food web right at the root zone of your plants. This is to harness all the benefits a functioning Soil Food Web can provide.

The ability to make extract microorganisms from composted material is coupled with the chance to multiply their numbers rapidly before applying them to the soil. We need to understand the difference between these two methods as they are very commonly misunderstood. Both require good starting inoculations which is our compost and the same water extraction process, but they do differ after that.

  • 1. Compost extract – After creating the compost extraction we have limited time to use the solution. The oxygen levels should be treated like a stopwatch that is counting down. Ultimately you want to use this as soon as possible to ensure the effort you took to keep the compost aerobic is worth it. Limiting the time to the application from making the extract to a maximum of 90 minutes is advisable, in this case, fresh is the only way.
  • 2. Compost tea – Once again we have made the liquid extraction of the compost but this time, we are looking to increase our microbial numbers. This is done by having the correct equipment and microbial bio-stimulating food sources. The equipment process is detailed and requires attention to all parts of the process with a chapter dedicated to all the requirements. However, the compost extract needs to have constant sources of oxygen to keep the right set of microbes active. Along with good environmental conditions, these microbes must be fed with their preferred foods which is also an area which requires an understanding of the different groups we are looking to breed out. Once we have achieved both good environmental conditions and plenty of food supplies life does what it was designed to do and replicates rapidly. This process is roughly a 36–48-time frame where we ‘brew’ the compost tea. Having a microscope to assess the development of these microbes is vital to assess their quality. This can be seen as supercharging your starting inoculation before using it and is the best way to turn a small amount of compost into highly effective soil-building inoculation.

We can redevelop these healthy soils that need rapid regeneration. Many pests, plant pathogens, disease-causing fungi or soil contaminations are problems that can be addressed with targeted inoculations of the processes that can achieve significant results in the regeneration of soil that has been overworked or contaminated. By understanding specific microorganisms and their role in healthy soil right microorganism.

Equipment requirements

There are several specifications for using this technology, especially with compost tea brewing and the application of that inoculum. All processes need to have your biological numbers in mind, from valve pressure to the type of pipes which you pump the compost tea through. There are many examples of different systems to fit all sizes of operation. Getting track of your biological numbers as you make compost and regenerate soil is where Microbial Bio-mass assessments are pivotal to determining if the right microbes are present.

Image 10: A picture of a large, but very neat composting operation

Potential of long-term applications for Soil health

Many Organic and Regenerative farmers have been turning to using this tool to build soil fertility at the lowest cost of production while maintaining yields. The effect of these microorganisms continues as the system develops, banking on soil quality to provide continual returns. Looking at long terms sustainability two things are clear. Prices of fuel and synthetic nutrients are rising. If a farmer could buy fewer synthetic nutrients and pesticides along with spending less fuel money on applying those inputs their business model would be far more sustainable. This is what focusing on soil health and low-cost regenerative practices can help you achieve. By understanding the composting process, creating high-quality inoculations which you supercharge before applying and putting soil health first you can achieve consistent yields with a cost model that diminishes over time. If the soil is managed correctly the need to produce compost inoculations is also something that reduces once the soil is functioning. Applications can be done to ‘top-up’ the populations, but good soil management should see their populations sustain themselves for years to come which is the ultimate goal of any regenerative farmer.

More information

If you would like to learn more about soil health through biological farming methods, contact SoilScopes for a free consultation call. Offering a range of services along with microbial biomass testing we can help you regenerate your soil. By investing in your soil, you can reap sustainable growth of your crops and your operation.

If you are interested in our services find us at
Or contact me directly on 074 616 0451
Wesley Soule
Owner of SoilScopes and Lead Consultant.