Well... I think all the scientific evidence necessary is out there in the plants' natural environment! No one is going out there dosing orchids in the wild with man-made fertilisers
If you find a source for something like this in Europe, please let me know, as I would switch in a heartbeat! I do use an organic seaweed foliar spray that is used in much the same way as this is described. But for regular feedings of the orchids, I'm still using the stuff from Kew Gardens.
I only use my own compost to feed my garden outside, and I only use plant based Ecover cleaners inside (laundry detergent, washing up liquid, window cleaners, everything), so I'd love to find something like this to use on my orchids inside. I'm quite careful about watering when I fertilise now, to ensure none of it goes down the drain (one of the other benefits of having the orchids in tanks) but I'm also conscious of the fact that this could cause salt build up in the bottom of the tank...
I was planning to start a wormery this spring to supplement my compost bins, and if there were a way to easily ensure the concentrations of NPK in the worm castings, I'd make my own!
Orchid133, thanks for the additional info!! That's just the information I was searching for....
PS. I can't believe they are being sued - that's just silly.