Orchid Growing Substrates

Orchid Growing Substrates
Introduction
There is a wide range of potting materials that can be used. In the old times, composted Oak leaf was used,
so were the osmunda fern fiber and sphagnum. Worldwide a wide range of potting mixes have been and are
used, from dried fern leaves in Indonesia to shredder tyre, through Rockwool, glass beads, bark, sphagnum,
peat, loam and the list goes on…
Whilst there is at least one grower in the world having ‘success’ with each and every of these components,
there must be a scientific basis on the use, and the eventual blending of the components. Some very
common products in one region are an absolute rarity in some others. Tree fern fiber is exceedingly common
in Vietnam and China, but exceedingly rare in England, where it needs to be imported. On the opposite,
Rockwool produced in Europe and readily available is very rare in Indonesia.
To most growers, hobbyists and professionals alike, one potting mix material is the same no matter the
source. Sphagnum from Europe, the USA, New Zealand, Chile and China make up for only one type in most
grower’s mind. Red lava rock, bark, peat represent in most people’s minds ‘one’ compound, where each is not
a component, but a category comprising vastly different products.
Recently, in Europe, the mindset has changed. After several massive storms over the last few decades, a lot of
pine tree forests were severely damaged. The growers, who ordered ‘pine bark’ for ages, suddenly got pine
bark, but it did not behave the same way as it did before. The trade called this type ‘storm bark’, because it
was from weakened, sometimes already dead trees. A few years later, ‘juvenile’ bark came on the market,
from younger tree plantations. The growers were buying one bark, one size, but at the end realized they got 3
vastly different materials, with vastly different behaviors. It was the awakening, which was tampered only by
the sellers, explaining that, in fact, they were the ‘same product’, and made hidden adjustments to try to keep
their customers. In America, the bark suffered the same fate too, where one of the best bark producers
decided to stop its production for orchids, and most other companies decided to reserve some batches of
their mulching bark for the orchid growers, instead of doing a specific product as they did before. It has been
the time of the coconut chips too, which were supposed to be wonderful, and would replace within ‘a year or
two’ according to their promoters, the bark from all around the world. They were economic, ecologic, a true
‘green product’, and working wonderfully… not. It did not happen, mostly because in a lot of cases, the
suppliers, the traders, the sellers, and the growers have different objectives and thinking, and different
results. A supplier is successful if he sells a container of coconut chips, but a grower is successful if his plants
grow well. So the supplier can deem a good success, but the grower, on the same container, can kill his plants,
like it happened countless times, and be on the verge of bankruptcy.
There have been a lot of companies, catering to either the pot plant trade, or the hobby trade, and even some
really famous orchid growers, which collapsed partially or fully because of the potting mix. In fact, all of this is
easy to explain, and that’s what we are going to do here.
Xavier Garreau de Loubresse
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