Soil is defined as the naturally occurring, unconsolidated mineral or organic material at the surface of the earth that is capable of supporting plant growth.
So what is soil?
I believe that it is vitally important to have a strong foundation to build upon when you are attempting learn about something , in the case of gardening that foundation is the soil. Without soil there would be no gardening as we usually think of it.
Talking about soil can be a very technical and sometimes lengthy subject. To understand how to be a Master Gardener you need to understand some of the science as well to build your foundation. This article will give you the knowledge base you will need to understand soil in clear, simple, and uncomplicated terms.
In General There Are Three Types Of Soil
- Sand – Mostly granular and is composed of rock particles and minerals. It does not retain water very well but is needed for drainage. Sand particles are large enough to be seen by the naked eye and have a grainy feel to them.
- Silt – A fine grain granular material derived from rock the larger particles are barely visible with the naked eye the smaller ones will require a microscope. It feels like talc when rubbed between two fingers
- Clay – It has very fine-grained minerals and high water content the particles are smaller than silt and also comprised of nutrients that are not available in organic matter. When wet, clay is very slick and feels a bit like plastic when dry it feels very hard and harsh.
- Organic Matter – There is one other component of soil and that is Organic Matter which is a combination of decomposed and partially decomposed plant and animal tissue as well as the dead and living tissues of microorganisms. Organic matter holds a lot of nitrogen, phosphorus and sulfur which become available to plants as the organic matter breaks down. Also of note organic matter works to increase the water holding capacity of the soil as well as helping with the aeration of the soil and produces food as it breaks down that feed the microorganisms who produce the chemicals that hold the soil particles together making it stable.
The easiest way to explain this is that the ratio of each of the four elements above determines the type of soil you have.
- Sandy soil consists of large particles that are great for aeration and drainage but will require organic material to make it easier to cultivate.Because it drains quickly it will need a lot of watering during the summer months and if you are not diligent the plants could wither and die.
- Silty soil is made up of minerals and organic matter while still gritty like sand the organic matter gives it a better nutrient value.Gecause of it’s fine particles when wet it could become compacted.
- Clay soil is probably the hardest to work with as it has the smallest particles and very little air spaces. When dry it is very hard and difficult to cultivate. Most times it will need to be amended to make it suitable for growing in.
- Loamy soil is a mixture of sand silt and clay and it is consider to be the best soil for gardening. The perfect soil for starting a garden in
- Peaty soil is composed of more organic material than any other type and it is very acidic. This prevents the organic materials from decomposing. The soil waterlogged easily and can cause root rot on your plants.
- Chalky soil is very rocky and dry it is also very alkaline. A very poor choice for growing plants in.
Finding The Right Soil Thank Goodness For Amendments
That is the eternal quest of gardeners is to find the right soil. Using the information above it should be easy to determine the best soil for gardening is a loam to sandy loam soil. If you are stuck with all clay or other not so desirable soil do not get discouraged.
Having poor soil is not a hopeless situation and you can easily amend it to make it suitable. It is important to note if you are trying to amend clay soil you need to be careful to add enough amendment or you might end up with harder soil. A great mix is 40% sand 40% silt 20% clay but many other combinations are still suitable and productive. To be able to amend the soil you need to know how much of each of the three components are in it.
A simple test will tell you what type soil you have. Place about 2 cups of soil in a large jar and then fill it the rest of the way almost to the top with water. Put the lid on the jar and shake vigorously for about 4 or 5 minutes then set the jar where it will not be disturbed. After 24 to 48 hours most of the soil will have settled into 3 layers sand on the bottom silt in the middle and clay on top. Now you have a good profile to work with and will know what you need to add to improve the soil using the 40-40-20 model.
Plants will grow in all types of soil but not all soil will support all types of plants. Master Gardeners know that you can grow plants by manipulating the environment an example would be bog plants which can be grown by building a bog area around a pond or a pond-less water feature.
In future modules we will be looking at specific ways that you can amended the soil or the environment to suit the plants that you want to grow and how to provide optimum growing conditions.