From pH 7 to 0 the soil is increasingly more acidic and from pH 7 to 14 the soil is increasingly more alkaline or basic. Soil pH provides various clues about soil properties and is easily determined.

Acid soils have a pH of below seven, neutral is pH7 and alkaline is above seven. Loamy soil - often seen as the ultimate garden soil because most plants will grow in it, this is brown and crumbly ...

The waste output generated by the extraction of metals like aluminium ... resulting in extremely alkaline and salty conditions that are difficult for normal living soil microorganisms and plants ...