All soils have some things in common. They are all made of mineral particles, organic matter, air and water – but soils are also different due to how and where they were formed. Five factors influence soil formation: parent material, climate, living organisms, topography and time.

The addition of organic matter to the soil usually increases the water holding capacity of the soil. This is because the addition of organic matter increases the number of micropores and macropores in the soil either by “gluing” soil particles together or by creating favourable living conditions for soil organisms.

Some experts think humus makes soil more fertile. Others say humus helps prevent disease in plants and food crops. When humus is in soil, the soil will crumble. Air and water move easily through the loose soil, and oxygen can reach the roots of plants.

clay soil

Water holding capacity in different types of soils is different. Soil absorbs water because it is porous. Sandy soil holds less water than clay soil and loamy soil.

Sandy soil drains more readily than other types of soil. Sand drains so quickly that extremely sandy soil needs to be watered more often because sand will not retain water long enough for plant roots to have good access to the moisture before it drains away.

Organic Material (Compost or Manure) Organic material is the most common and well-known additive to improve soil drainage. Soil drains better when it contains more organic material, such as compost, manure, and mulch. Good compost is worth its weight in gold – well, at least in your garden.

Sandy soil drains more readily than other types of soil. Sand drains so quickly that extremely sandy soil needs to be watered more often because sand will not retain water long enough for plant roots to have good access to the moisture before it drains away. Sand is useful for drainage.

Sand is one of the cheapest things you can add to your garden soil that will help to break up the soil. The small particle size of the sand will get in between soil clods and break them up, increase drainage, and help to aerate the soil for good root development. Mulching can do miracles for your soil.

What Does Well-Drained Soil Mean? Simply put, well-drained soil is soil that allows water to drain at a moderate rate and without water pooling and puddling. These soils do not drain too quickly or too slowly. When soil drains too quickly, the plants do not have enough time to absorb the water and can die.

Clay soil is soil that is comprised of very fine mineral particles and not much organic material. The resulting soil is quite sticky since there is not much space between the mineral particles, and it does not drain well at all.

The water gathers until no air space is left. Once all the available soil air space fills up, then excess water drains into the gravel below. So gravel in the bottom does little to keep soil above it from being saturated by overwatering.”