Dr. Russell Sharp of Eutrema explains why most gardens and sports pitches contain some clay, how the soil texture triangle works, and why liquid gypsum helps by flocculating clay to improve drainage.

He gives simple DIY tests (jar sediment test and the ribbon/ball test), recommends using soil maps or neighbor knowledge, and advises working with your soil rather than trying to change its texture.

https://eutrema.co.uk/shop/soil-conditioners/liquid-gypsum/