Orchids in the wild - how do they grow in sand?

[mark smyth]

I was out and about today.

How can Pryamidal and Common spotted grow in pure sand?

How can Northern marsh orchids grow on/in a scree below a limestone quarry face.

And going back to May how can Early purples grow in/on a pile of road stones, basalt chips, at the side of the road?

[Chuck]

I am currently growing my Cypripediums in a sandy mix with perlite, some peat, and lava rock. The sand is really great for drainage and is especially useful to prevent water logging.

[mark smyth]

where does the food come from?

[daveyp1970]

Mark in the wild its all down to mycorrhiza with out it the orchid wouldn't germinate but i think in such harsh conditions as pure sand ect i think the orchid relies heavily on it's mycorrhiza even when its an adult.
Also i think in sand there are still tiny particles of rotting plant matter ect blown in and trapped that slowly releases nutrients.

[Chuck]

where does the food come from?

It comes from bird droppings, dead insects, the rain, and decomposing debris.