Rugby Club Issue 67 | Page 11

A Guide to Drainage A Guide to Drainage SOIL and WATER – BACK to BASICS By Bruce Brockway, Secretary Land Drainage Contractors Association We all know what we mean by ‘soil and water’ but it only refers to two of the three ingredients necessary for plant growth – the third being ‘air’. If you only have the first two you have a drainage problem! The purpose of drainage could be said to introduce air into soil. Soil Particles Soil has mineral particles of different sizes. The smallest are clay particles, next are silt, the largest being sand. Whilst some soils can have only one Plant roots need soil, water and air to be able to size of particle like pure sand, most soils will have absorb nutrients from the soil. As a growing medium a mixture of particles. Soil texture is classified soil should consist of roughly 50% particles, 25% according to the respective percentage of these water, and 25% air. The water and air should be in particles. For example if a soil is 60% silt, 20% the spaces between the particles. sand, and 20% clay, the soil texture is described as ‘silty loam’. www.rugbyclub.biz 11