Topsoil is an important component of most landscape projects (such as private gardens, civil engineering and reclamation sites), where it provides the function of supporting the growth of vegetation. It does this by providing an anchorage for plant roots, by slowly releasing nutrients, by providing oxygen, by draining excess water whilst retaining moisture and by retaining moisture to sustain plant growth during dry periods. The underlying subsoil or other substrate can provide additional rooting depth, moisture storage and drainage.
BS 3882:2007 specifies requirements for topsoils that are moved or traded. BS 3882 is not intended (or appropriate) for the grading, classification or standardization of topsoil or subsoil that remains in situ.
BS 3882 describes multipurpose and also specialist purpose topsoils. As the name implies, multipurpose topsoil is fit for the majority of needs. It includes specialist purpose topsoils that have low fertility or are acidic or calcareous for the particular specialist needs where such topsoils are required.
BS 3882 also gives guidance on sampling and analysis to ensure compliance with the specifications outlined in the standard. When specifying multipurpose or specialist purpose topsoil, suppliers, specifiers and users of topsoil should take into account the intended use of the site at which the topsoil is to be deployed so that the particular properties are fit for the intended planting.