• Composition: crushed spongilite, compost
• Intended use: for undemanding plants such as mosses, sedums, and certain other xerophytic perennials and grasses that can go without watering for long periods
• Layer thickness: 4–20 cm
• Advantages: very good water retention capacity and sufficient permeability

When combined with coarse spongilite (16–40 mm fraction) at a ratio of up to 40% by volume, the substrate is also suitable for filling growing panels (up to 10 cm wide) in vertical green walls.