Rootshield aka trichoderma harzianum

[Lars Kurth]

Hi everybody,
on the UK Orchid forum a forum member made the following comment recently:

Hi all, I´ve recently been experimenting with trichoderma harzianum which is a parasitic fungus that seems to work rather like a symbiont, it protects the plant roots from fungal and bacterial pathogens and as well enhances the performance of the plant. It´s marketed as RootShield in the US ...

I was wondering whether this is something any of you have experience with?