Volcanic clay gravel is available in two colors: red and black. Both variants share the same extra-coarse particle size (10–20 mm) and the same 25 kg bag format, meaning their agronomic function is identical: aeration, drainage, and top dressing in pots and gardening. The choice comes down to aesthetics and the contrast you are looking for with your plants or the design of the space.
Comparison | Volcanic Clay: how to choose the right variant
