John Varigos wrote:
I am thinking of buying some Disa flasks from a supplier but on visiting the
web page and looking at the cultural information, I note that it says
"Fluoride in the water is thought to be toxic."

Melbourne's water if fluoridated and I have been using it for over 30 years
on my orchids without seemingly any ill effect.

Can anyone enlighten me as to whether there is any truth to this statement
especially for Disas. I'd hate to spend the money on buying the flasks and
having every seedling facing a death sentence as soon as they are deflasked.


I do grow disas and have for about five years now. I can only tell you
what I have been told by others who have grown them longer and studied
them. They need as pure water as you can arrange. I have been told that
TDS must be kept below 200ppm (even with fertilizer in it), better yet,
below 100ppm, to successfully grow them. As my tap water tests out at
265ppm (nmysteriously, as the first year it tested at 412ppm), I use
rainwater which tests for me at 11ppm.