It's
http://www.esveld.nl they are situated in Boskoop in the Netherlands.
They ship to the whole world, in spring before budbreak, and in fall after leafdrop, i.e when the plants are dormant.
I spent some time talking with someone from the family and they've got very interesting things to tell about their soil. Apparently they've switched to an organic system using EM Effective Microorganisms together with clay minerals, bokashi and chalk from seashells. They've gone from 10% loss in 15000 plants per year, to 6 plants (not a percentage!) lost this year so far, If what he said is true.
Especially effective in making maples resistant to Verticillium and other wilting funguses.
I did ask, and was told that this combination was totally applicable to potted plants as well, and used just for that purpose by them as well.
The clay minerals provide certain nutrients,
the bokashi contains come nitrogen in usable form and is a great medium for the microorganisms, and the chalk balances the ph level.
Does anybody have any experience with this? Or knows more about EM?
Check these links on Effective Microorganisms.:
(recepies included)
http://en.wikipedia.org/wiki/Effective_Microorganisms
http://www.agriton.nl/homeeng.html
http://www.emnz.com/bokashi.html