Hi there -
The majority of my hostas are planted under the drip line of a very small apricot tree and some kind of flowering bush. A few others share the shade between a birch and a small plumb tree. They have been there three years now, and they are growing
, but not much. The North side of my house is basically the property line, so I don't plant anything over there. My beds are on the South and East sides of the house, primarily.
I don't think any of them are dwarfs. All of them were acquired from either a nursery or splittings from my neighbors. Still, is 6-8" measured at the roots or the leaves? If it's the leaves, I'd say all of them are that big or bigger. The root bases are probably only about 3-4". I am so envious of my friends with a little sun. One of them planted last year and has one that's at least a foot across at the roots. Sheesh. Can a girl catch a break around here???