| 摘要 |
A rock wool growing medium incoporates a surfactant and a sparingly soluble inorganic material, which gradually dissolves in nutrient solution to provide benefit to the plant. The inorganic material may for example provide silica to enhance plant growth or silver which is a fungicide. The incorporation of the inorganic material in the medium avoids the problem of precipitation in supply systems associated with attempts to dissolve such material in a conventional nutrient supply. The inorganic material may be incorporated by spraying or sprinkling onto a primary mat of rock wool 19 through the surfactant spray 24 or by a conveyor 25. Substantially uniform distribution of the inorganic material then occurs during formation of the multi-layer mat 23 and subsequent compression, crimping and air curing. |
