Do Paphs need limestone in their mix?

[NYCorchidman]

That's what I mean!

Wrong date from wrong place, or just a speculation based on the observation of how some paphs grow on lime stone rock.

Local growers still tell their customers to add lime stone to the paphs (these are maudiae type hybrids). I almost laughed and cried. lol

[lepetitmartien]

I may sum up (IMHO) that having a plant growing is slightly acidic to neutral conditions on or near limestone means it has a regular source of Ca around, I think it's the important point. That it's in the fert, the mix or the water as long there's enough (not necessarily tons) and in an available form is what counts.

Else we'd grow them directly on limestones "à la samouraï"

On the lack or overdose of oligo-elements, check on Sue Bottom's page at STAUG:
- Choose your fertilizer…
- Calcium and Magnesium

Orchid Culture Articles - Sue Bottom

[Suri85]

Here in Jakarta, paph is one of the hardest to grow. Recently almost everyone here suggest pumice rock, haven't tried it before, any thought?