Osmunda fiber is the root system of the royal fern Osmunda regalis. It's a very tough one, brittle material of good durability and excellent ventilation; hardly contains any mineral components: disadvantage: relatively high price. Most used internationally at the moment.
Polypodium fibers are the roots of the polypodium vulgare. Compared to the Os-munda, a very fine one, soft material of poor resistance and ventilation, the addition of earthy components can hardly be avoided. Due to these mineral admixtures, Polypodium appears somewhat more nutritious than Osmunda. Use only to a limited extent, for small orchids, however, an indispensable condition for attachment for block culture.
Swamp moss = Sphagnum squarrosum, like the substrates mentioned above, cannot be used on its own, but is mixed in a differentiated ratio. Relatively large water storage capacity, low degree of reaction in the acidic range. disadvantage: rotting quickly, Danger of the introduction of snails.
Beech leaves – collected in autumn and kept dry – is a good addition up to 20% for epiphytic and terrestrial orchids.
These “classic” plant materials are contrasted with those used in recent times: Tree trunks in sections for planting or grated as a substrate correspond roughly to the Osmunda fiber; the structure is even harder, overall more even and without mineral admixtures. Pine bark is an equivalent substitute for the bark of some species of fir, which is widely used in the USA, marketed as "Wonder-Bark". The bark must come from older pine trees, so have a certain strength. After mechanical shredding, they are sorted through sieves in three sizes. Before using is a several hour soak in one 1 to 2 A strong complete fertilizer solution is appropriate, to add nutrients to the material. Pine bark has many advantages: good ventilation, slow decomposition (approximately 4 Years to complete disintegration), great water-holding capacity, low price.
Peat is the plant material with a great future. It has already been tried and tested many times; the successes are for the most part excellent. Its cheapness is an important factor in large-scale gainful crops, especially for the planting process. Only less decomposed sphagnum peat from younger raised bogs should be used, so a coarse-fibrous material. This plant material is less suitable for the orchid lover, since continuous control of the nutrient ratio appears to be necessary.