Soils
Most of the time when we talk about our garden we mention the plants or the structures that we have in our garden, and almost never about the most important thing that make our garden exist: the soil. Soils are highly complex and dynamic materials that are made up of particles of weathered rock and organic matter, also known as humus, as well as plant and animal life.
For a successful development of our plants we need a healthy soil. The soil is the support and the supplier of food for our plants so it has to be in perfect condition in order to be able to offer the water, air and mineral nutrients to the plants that we grow in our garden.
Not every garden has the ideal soil but we can always improve the quality of our garden soil. There are many solutions that require little time and effort and can help us to bring the soil to a better condition. And there is always a second choice. Growing plants in containers is the best solution where the soil is in such a bad condition that don’t worth the effort to try to improve it. When you grow plant in containers you can always choose the right soil for every plant.
Soil types by structure
Soils are classified according to their clay, silt and sand content. The size and proportion of these mineral particles affects the chemical and physical behavior of the soil. The main categories of the soil are: loam, clay, sandy, silt, organic or peat, chalk or limestone soils. Most garden soils are combinations of several of these types and it can vary in different parts of the garden, so is possible that your garden will have different type of soil in different places.
Loam soils have the ideal balance of mineral particle sizes, with an amount of 8 to 25 per cent clay. This means that it provide good drainage and water retention to the plants and it also is highly fertile. This is the type of soil that any gardener wants to have in its garden as this is what we call good garden soil. It can be helped to maintain its fertility by adding organic matter.
Clay soils have more than 25 per cent clay particles. They are wet and sticky, often highly fertile but heavy, with slow water drainage. They are easily compacted, warm up slow in spring and may bake hard in summer. This type of soil can be easily improved with the addition of well-rotted organic matter, gritty sand or fine bark chippings. This will help to improve the soil drainage, aerate the soil and makes it easier to work.
Sandy and silt soils have low proportion of clay particles, usually under 8 per cent, so they are much less water-retentive than clay. Sandy soils are dry, light and free-draining, easy to work but relatively infertile so they need frequent irrigation and feeding. They warm up quickly in spring and can be easily improved with a good addition of organic matter. Silt soils are more retentive and fertile than sandy soils but tend to compact more easily.
Organic or peat soils are wet - as they are moisture-retentive, dark and acidic but they support excellent plant growth if they are drained, fertilized and limed.
Chalk or limestone soils are pale, shallow, stony, free-draining and alkaline, with moderate fertility, allowing organic matter to decompose rapidly.
It is important to know what type of soil you have in your garden. You can identify your soil by rubbing a small amount of moist soil between your fingers. If the soil is sandy it will feel quite gritty and will not stick together or form a ball because the sandy particles will not stick together. A sandy loam is more cohesive. A silt soil feels silky or soapy to the touch. A silty loam may show imprints when pressed with a finger. A loamy clay soil will hold together well and may be rolled into a cylindrical shape. Heavy clay soil may be rolled even more thinly and develops a shiny streak when smoothed. All clay soils feel sticky and slightly heavy.
