Soil texture is defined as the size distribution of different mineral particles. These mineral particles are at their most basic level the following: sand, silt and clay. Sand particles are 2 to 0.05 mm in diameter, silt particles are 0.05 to 0.002 mm in diameter and clay particles are 0.002 mm in diameter. Combination of these particles exhibit different properties in soil and some combinations favor plant life better than others. The following are the most common soil textures:
Clay soil contains a high percentage of clay particles and feels lumpy to the touch. The small size of the clay particles means that they clump together quite easily and there is less room for air spaces. Consequently, clay soils have poor drainage and do not hold nutrients very well. Clay soil is heavy and sticky when wet making it hard to work with. As much as possible you should take steps to improve the drainage of this type of soil.
Silty soil contains a high percentage of silt particles and feels smooth to the touch. Silty soil is a well draining soil due to the particle sizes which allows space for water to permeate. This soil holds nutrients more readily than clay soil due to these spaces. Silty soil is easy to cultivate but can be compacted quite easily.
Sandy soil contains a high percentage of sand particles and feels gritty to the touch, Allowing for quite a lot of space in between particles and as a result is very free draining. This has its disadvantages since it does not hold water and essential nutrients can be washed away.
Loamy soil is the best soil texture you can have in your garden. The properties of loamy soil are controlled equally by the percentages of clay, silt, and sand particles. It is well drained but does not loose water too easily as sandy and sometimes silty soils. The fact that it retains water means it also retains nutrients for your plants. Loamy soil has a great structure and is easy to cultivate.
If you would like to learn more about the way water drains through different types of soil, read our article on Soil Permeability and Infiltration.