Compost Vs. Soil

Compost is made up of organic material, while soil contains the same plus inorganic materials such as rocks and minerals. This guide will take you through all you need to know about soil and compost, their differences, which one to use in each scenario, and when growing crops.

What Is Compost?

Compost is a nutrient-rich mixture of organic matter that has undergone the decomposition process. This process recycles organic material ranging from plants to animals and just about any living organism. The organic materials used can also be from waste material such as leaves, grass, and food scraps. These get decomposed by fungi, and aerobic bacteria break into humus, which is further broken down by detritivores and earthworms and redistributing the nutrients in the entire hip of compost. This process can be aided by regularly turning the compost.

What Do You Use Compost For?

1. Boosting Nutrient Availability 

Compost is rich in essential nutrients such as phosphorus, nitrogen, and potassium. These nutrients occur in very low quantities naturally in the soil, and over time they get leached from the soil leaving the plant’s roots without any access to the essential nutrients. Adding compost that's rich in these big three nutrients will give the soil a substantial nutrient boost, which will be available to the plants in natural quantities.

2. Improved Soil Structure

Organic matter in compost increases the number of air pockets in the soil, which allow the nutrients and water to flow through the soil unrestricted to areas of low concentration, such as near the plant roots. Improving the soil structure also makes it much easier for the plant roots to grow more densely, which further enhances the absorption rate of the essential nutrients.

3. Better Moisture Retention

Soil that's been fortified with compost retains more water and for a more extended period compared to bare soil. This is thanks to the air pockets created by detritivores and earthworms in the compost and surrounding soil - these paths redistribute the water evenly, the moisture that would otherwise drain off quickly or evaporate at the surface of the soil. 

4. Balancing The Soil pH

Mature compost has an almost neutral pH level, which helps offset any acidity or alkalinity that may exist in your soil. Compost compounds do not contain excessive acidity or alkalinity. This makes it much more palatable for your plants while also encouraging soil microbes’ growth, which help in nitrogen fixation and keeping harmful cultures at bay.

5. Healthy Natural Soil Organisms

Compost contains a lot of nutrients that often attract small insects and other soil organisms to the soil that's been fortified with compost. These serve various roles in the micro-ecosystem, from nitrogen fixation to removal of harmful microorganisms in the soil that would otherwise invade the plant roots. The organisms also help distribute nutrients in the soil and create airways in the soil around roots, increasing soil’s water retention and the soil aeration and water redistribution.

6. Mulching 

Mulching with compost serves to preserve the soil’s water retention and provides a continuous supply of essential nutrients. Well composted humus is often dense, preventing water from evaporating directly into the air; instead, it recondenses back into water droplets in the numerous air pockets found in compost.  Mulching with compost on a drip irrigation setup will also prevent evaporation while also preventing weed growth.

7. Boosting DIY Potting Soil

Compost packs a large quantity of essential nutrients that potted plants require making it a great addition to potting soil. Compost releases the nutrients slowly over time, unlike artificial fertilizers, which quickly release the nutrients making them more susceptible to leaching. Adding compost to potting soil will also introduce natural soil organisms that help in increasing soil aeration.

8. Preparing Compost Tea

Compost tea is an organic fertilizer that's obtained from brewing compost with water. The process requires mature compost, which should be free of any harmful pathogens to provide essential nutrients. The compost is mixed with water and at least one ounce of molasses to provide additional nutrients for the compost’s live cultures. After three days, the water will have been enriched with billions of useful cultures and essential nutrients from the compost - this brew can then be watered around the base of the plants for the best results. Further reading material: link.

9. Top Dress Garden Beds

Topdressing is the process of adding a fresh layer of soil enriched with compost. Topdressing garden beds and potted plants introduces a fresh supply of nutrients for your plants to feed on. Enriching the topsoil with compost ensures that the nutrients get released slowly over time in naturally balanced amounts. Topdressing with compost-enriched soil also introduces the necessary microorganisms that help eliminate harmful pathogens.

Different Types Of Compost

How To Find Quality Compost

1. Check The Temperature Of The Compost

Decomposing organic matter in the compost provides nutrients which the microorganic cultures feed on releasing heat- a healthy pile of compost that’s about 2 feet deep will produce enough energy to reach anywhere from 90˚ to 140˚ F for the first 2 to 4 weeks, after which the heat will gradually reduce as the cultures run out of nutrients to feed on. 

2. The Smell Of The Compost

This is probably the most concrete way of identifying mature compost - it should never have a pungent odor, which indicates that decomposition has not fully occurred. Instead, the best compost has a rich decomposing wood scent with hints of freshly turned earth. This indicates that decomposition has fully occurred, leaving the nutrients freely available to the plant’s roots while also eliminating all pathogens in the compost.

3. Check The Colour Of The Compost

Good compost has a light brown to a dark brown hue and a crumbly texture that's soft to touch. Fully matured compost should also be relatively dry such that it crumbles between your fingers. This indicates that the bacteria and yeast cultures in the decomposing organic matter have broken down most of the organic content releasing more nutrients into the compost.

What Is Soil?

Soil is a material that comprises five main ingredients: minerals, water, air, living organisms, and soil organic matter (plant, microbial, and animal residues). Further reading material: nature.com

What Do You Use Soil For?

1. Agriculture

Soil contains all of the essential nutrients that plants require to grow - having fertile soil is considered to be a bonus in agriculture. You can increase the soil’s fertility by using organic compost or artificial fertilizer depending on the specific needs. Soil should also be well-drained to prevent waterlogging, which increases the rate of mineral leaching.

2. Construction

While constructing structures on land such as houses having well-compacted soil with proper drainage will guarantee long-lasting foundations. Soil is also a key ingredient in the manufacturing of red bricks which lowers the overall cost of production and construction.

3. Pottery

Clay soil is required in the process of making ceramics where it's mixed with water and molded into the shape needed before the drying process can commence. The clay should undergo a firing process in the kiln to harden the surface.

4. Beauty Products

Soil is at times used in the production of beauty products such as blush, foundation, and facial masks.

5. Medicine

Soil contains healthy microbes that are cultured in labs to extract antibiotics for various treatments including skin oil ointments, anti-tumor drugs, and even tuberculosis drugs

Further reading material: sciencing.com

Different Types Of Soil [Top Soil, Potting Soil]

1. Top Soil

Topsoil is the upper layer of soil that is rich in organic matter and living organisms. Topsoil lays around 5–10 inches (13–25 cm) deep. It can be used to topdress plants after enriching it with compost.

2. Potting Soil

Potting soil is a medium on which plants can be grown on in pots. It comprises sand, peat moss, bark compost, organic compost, and leaf mold. This combination provides a constant supply of nutrients to the potted plants and can be enriched over time with compost. 

Further reading material: link

How To Find Quality Soil

1. Presence Of Soil Organisms

The presence of soil organisms indicates increased soil fertility and fewer pathogens. You can dig a hole at least 6 inches deep and watch the hole for about 5 minutes. Keep track of the critters you see in the hole, such as centipedes, worms, spiders, and ground beetles. The presence of earthworms indicates that the soil is not only moist enough to sustain them but also contains decomposing humus which the earthworms feed on. These increase the aeration rate in the soil and leave behind excrements that are full of nutrients that are readily absorbed by the roots.

2. Structure Of The Soil

The structure of the soil is mainly determined by the hardness of the tilled soil. A healthy soil consists of different chunks with varying levels of hardness. The best soil structure can be observed in organic roam soil with rounded aggregates that allow air and water to circulate more easily around the roots. On the other hand, hard to break aggregates, on the other hand indicates a soil problem that needs to be resolved by applying the farmyard compost.

3. Workability

Soil workability takes into consideration how easy or hard it is to till the soil, and how compacted the aggregates are- these require extra work to soften and additional compost to increase the aeration. It's essential to pick well-aerated soil with increased workability so as to reduce the labor necessary to prepare the soil in readiness for planting. Additionally, easy to work on soil often results in increased harvests due to nutritional availability.

4. Water Infiltration

Water infiltration is a measure of how water reaches the plant roots from the soil. A simple DIY water infiltration test involves removing the upper and lower covers of a coffee can and implanting the open tin halfway deep into the ground. The remaining part is then filled with water, and its height is measured. After one hour, the height of the water is then checked, and an absorption rate in inches per hour is calculated. If the rate is slower than 0.5 - 1 inch/hour, then the soil is likely to be compacted, which reduces the water infiltration rate.

5. Compaction

Compaction refers to how densely packed the soil is relative to air and moisture content. Compacted soil restricts the free flow of air and water through the soil while also constricting the development of roots. This leads to reduced harvest and increased germination failure. Compacted soil requires it to be dug up at least half a foot deep and mixed with compost to improve its texture and aeration rate.

6. Water Availability

Water availability tracks the rate at which the soil loses water naturally. Aerated soil has a reduced water evaporation rate allowing it to retain moisture for longer. You can test the water availability of the soil after a soaking rain. Water availability is critical as the plants rely on frequent water supply to grow and bear fruits and grains. If your plants require increased watering than what is typical for your area, there’s a high likelihood you are dealing with compacted soil.

7. Root Development

Healthy root development is an indication of healthy plants and fertile and arable soil. A quick and simple test to check root development involves gently uprooting a weed that's growing on the ground and checking how well the roots are developed. If the roots are less developed and seem constricted, this is a clear indication of compacted soil with reduced aeration, thus requiring additional compost before you can put the soil to use. Further reading material: link.

Differences Between Composting And Soil

1. Nutrient Content

Compost is much richer in nutrients due to the presence of decomposed humus and excrement that are left behind by microbial cultures as they break down the decomposing organic matter. On the other hand, the soil has lower amounts of nutrients due to exposure to the elements, especially heavy rains, which often wash away the topsoil and leach minerals from the soil.

2. Aeration

Aeration refers to how easily air and water molecules can traverse the soil- this is heavily influenced by the compactness of the soil or compost. Compost is much more arable compared to soil due to the presence of humus and earthworms, which burrow in the organic matter and create air pockets for water and air to pass through. Soil, however, has less aeration due to increased compaction and reduced population of critters that burrow through it.

3. Water permeability

Compost has a higher water permeability rate due to its numerous air gaps, unlike soil, which has a more compacted texture, and reduced air pocket switch would allow the water to permeate through. Water permeability heavily influences the growth of your plants as they need a constant supply of water, which isn't the case when the soil is too compacted.

4. Living Organisms

Compost contains more living organisms due to the presence of decomposing organic matter, which they feed on. Soil, on the other hand, has a reduced population of living organisms due to lack of nutrients and a more rigid texture that prevents the living organisms from burrowing in too deep. Living organisms are critical for breaking down the decomposing organic matter and leaving behind readily available nutrients.

5. Content

Compost continues a considerable quantity of decomposed matter, air, and water. In contrast, soil has higher levels of minerals and rocks that vary in terms of texture from large particles to tiny ones. Neither of these altogether provides the most optimal conditions for plant growth; instead, a mixture of compost and soil provides the best performance.

Similarities Between Composting And Soil

1. Presence Of Microbes

Both compost and soil have billions of live microbes that form colonies and feed on decomposing organic matter. Microbes are considered to be of added benefit to the farmer as they eliminate pathogens in the soil or compost that would otherwise harm your plants.

2. Humus

Humus is made of decomposed organic matter and is full of nutrients. In soil, most of the humus is found in the upper layer of topsoil and in large amounts when it comes to compost. Humus also contains the remains and excrements of critters that feed on the organic matter; this provides readily available nutrients for your plant’s roots.

3. Impact On Crop Yield

Having fertile soil that's enriched with compost will provide increased crop yields with much healthier plants. This is due to the optimal availability of nutrients for the plant’s roots to absorb. At the same time, the free circulation of air and water in the soil prevents the leaching of essential minerals.

Should I Use Soil Or Compost?

Further reading material: link

Factors To Consider Before Using Compost

1. Moisture Content

The presence of too much water in the compost is a likely indicator of incomplete decomposition. Mature compost loses most of its moisture to evaporation due to the increased temperature as the microbes feed on the organic matter and release heat.

2. Temperature

The temperature of compost relies on the level of microbial activity in the compost as they break down the organic matter. If the temperature of your compost falls below 90˚, your compost is likely not yet fully decomposed and needs more time.

3. Particle Size

Compost should have a crumbly texture that's smooth to the touch and easily crumbles between your fingers. Remnants of the organic matter that was composed can also be observed in the compost. Only go for compost with a crumbly texture as this indicates its fully decomposed, releasing nutrients and eliminating pathogens.

Factors To Consider Before Using Soil

1. Soil Structure

The best soil structure can be observed in organic roam soil, which has rounded aggregates that allow air and water to circulate more easily around the roots. Hard to break aggregates, on the other hand, indicates a soil problem that needs to be resolved by applying farmyard compost.

2. Soil Drainage

Soil drainage is highly critical when growing crops that are sensitive to waterlogging will-drained. Having well-drained soil prevents mineral leaching, which adversely affects growing plants and reduces their production. Proper soil drainage also prevents the occurrence of soil compaction, which interferes with root development.

3. Soil Profile

The soil profile will dictate the kind of plants you can grow on it. Clay soil is best for plants that require a lot of water, such as paddy rice, while roam soils are recommended for vegetables and fruit-bearing trees.

4. Soil pH

The soil pH describes the acidity or alkalinity of the soil, which is a significant consideration when picking the specific type of crop you want to grow. Soil pH can be changed over time by adding farmyard compost.

5. Presence Of Microorganisms

The presence of soil organisms indicates increased soil fertility and fewer pathogens. You can dig a hole at least 6 inches deep and watch the hole for about 5 minutes. Keep track of the critters you see in the hole, such as centipedes, worms, spiders, and ground beetles. The presence of earthworms indicates that the soil is not only moist enough to sustain them but also contains decomposing humus which the earthworms feed on. These increase the aeration rate in the soil and leave behind excrements that are full of nutrients that are readily absorbed by the roots. 

Mixing Compost Into Your Soil

What Is It?

This refers to the process of mixing in compost to soil in order to change its aeration and nutritional availability.  The ratio of compost to soil varies depending on the specific use whereby raised plant beds require a 50/50 ratio, during and ground plants require a 20/80 compost to soil ratio. 

When To Mix

The best time to mix compost and soil is during the preparation phase before the plantation process starts. 

Why Mix 

Mixing compost and soil introduces nutrient-rich humus to the soil as well as the microbial life in it, which goes a long way in keeping your plants healthy and growing optimally. 

Can Plants Grow In Compost And Topsoil?

Yes, plants grow best on topsoil and compost mixture as it contains required nutrients and water needed by the plants to grow.

Which Is Better For Plants?

Topsoil is better for plants as it contains a mixture of compost and soil for the most optimal supply of nutrients.

Should You Mix Them?

Yes, the best approach to plantain g involves mixing soil and compost in optimal ratios to increase the availability of nutrients. 

Which Contains More Nutrients?

Compost is much richer in nutrients due to the presence of decomposed humus and excrement that are left behind by microbial cultures as they break down the decomposing organic matter. Soil, on the other hand, has lower amounts of nutrients due to exposure to the elements, especially heavy rains, which often wash away the topsoil and leach minerals from the soil.

The Environment: Compost And Soil

Mixing compost with soil is a great way to deal with organic waste that can be composted, which is good for the environment. 

Which Should You Use For The Environment

A mixture of soil and compost offers the best balance of conservation of soil while still enriching it for farming activities. 

Common Questions

Can You Use Compost As Soil?

Yes, compost can be mixed with topsoil to work wonders on your plants. 

Should I Use Soil Or Compost?

A mixture of soil and compost is best suited for all plants.

Is Potting Soil And Compost The Same Thing?

Compost is just one part of the mixture that goes into making potting soil.

Can Too Much Compost Hurt Plants?

Yes, using too much compost can smoother plants and kill them by preventing proper aeration.

Can I Use Compost Instead Of Topsoil?

Yes, you can use compost instead of topsoil while topdressing.

What Is The Best Ratio Of Compost To Soil?

The best ratio of compost to soil is 20% compost to 80% soil or 1 container of compost for every 4 containers of soil.

Can You Add Too Much Compost To Soil?

It's not recommended to add too much compost to soil as it will smoother the plants.

Can You Plant Without Compost?

It's not recommended to plant without compost as the plants might not have access to enough nutrients in the soil.

What Is The Best Compost For Vegetable Gardens?

Farmyard compost is the best variety for vegetable gardens due to its long-lasting effect and high amounts of nutrients.

What Is Better Compost Or Fertilizer?

Compost has a natural balance of nutrients, unlike artificial fertilizers.

Can You Fill A Raised Bed With Just Compost?

No, a 50- 50 ratio of compost and topsoil is the best-recommended amount for raised beds.