Soils and layers
Sphagnum barrier layer
A mat of dried long-fibre sphagnum laid over the drainage to keep soil from falling into it.
What the simulation uses
- Holds water
- 70 % by volume
- Water it keeps after draining; the rest runs down to the drainage.
- Pore space
- 93 % by volume
- Room for air and water between grains; low means roots suffocate when wet.
- Weight
- 60 g/L
- How heavy a litre is.
- pH
- 3.5 to 5 pH
- How acid it keeps the soil.
- Mould risk
- low
- How much fresh food it gives white mould; high-risk soils fuzz over in the first weeks.
- Breaks down in
- 1 to 3 years
- How long it lasts before rotting down to fine soil.
- Nutrients
- low
- Plant food it brings.
- Presses down to
- 40 % of its loose depth
- How far pressing can pack it, keeping its weight.
Description
A mat of dried long-fibre sphagnum laid over the drainage to keep soil from falling into it. It holds plenty of water and helps slow mould. Expect it to break down over one to three years.
Also called sphagnum mat.
Estimated, where sources were thin: values estimated from hobby and horticultural references; not measured.