I have about 10% pine barks in my mix for the yew, Crepe Myrtle, Trident, and some other small stuff. My zone have quite hot and humid summers and I was hoping the organics hold moisture a bit better.
But I have collected Gojis and Privets in straight DE 8822, and they're growing like weeds. I'm gonna change to a more course inorganic mix this spring though and see if they do even better.