摘要 |
The substrate (1) has at least one layer of mineral wool and its surface which is designed to receive the plants has projections or recesses (4) in addition to the plant holes to provide a grip for trailing plants. The substrate has a density of 30 - 180 kg/cu m and a water retaining capacity of 50 - 95 per cent. The plant grip recesses can be, for example, in the form of holes whose depth is less than 90 per cent of the substrate thickness, having a diameter of up to 40 mm or a perimeter up to 120 mm, or in the form of grooves up to 15 mm wide. The recesses or grooves cover at least 3 per cent of the surface of the substrate which is devoid of plant holes. |