Tea blending is the blending of different teas together to produce a final product. This occurs chiefly with Black tea which is blended here with leaves that are from different regions before being compressed. The aim of blending is to create a well-balanced flavour using different origins and characters. This also allows for variations in tea leaf quality and differences from season to season to be smoothed out.
The one golden rule of blending is this: Every blend must taste the same as the previous one.