decorative pots .. and most of the plants you list.. will grow roots INTO THE POTS... if you dont move them every so often ...

your list of plants is ... 'the usual suspects' .. when peeps complain in the hosta forum ... about uncooperative trees ....

your problem is.. that every time you dig a hole.. you sever tree roots ... then you amend the hole.. and guess where the tree will grow new feeder roots.. right into the plant you planted ...

a real catch 22 ...

so think pots ...

ken

Ken is right about the roots growing right up into the pots. To prevent this put them on 'pot feet'. i've had success with gerarnium macrorrhizum, epimedium and most surprsing of all sedum 'Angelina' under two river birches that also have very dense root systems.

Just informationally speaking, in a large garden if you have troublesome tree roots, a middleplow/subsoiler on a tractor can easily cut them. Even my little Kubota subcompact has the power to break 2 or even 3" roots although it takes a bit of thrashing about and probably wouldn't be a good idea to do repeatedly. A bigger tractor would make easy work of them I suspect. Alternately of course you can rent a ditchwitch or similar device. It leaves a little mound that you can easily push back down with the rear tires.

I did this along a gigantic 80', 3' trunk diameter maple, the delineation was so stark that the grass beyond the cut roots stayed green all summer, while the grass closer in browned out from drought. It was an amazingly sharp line, like one side had been sprayed with roundup. Really showed how much water a big tree like that is sucking up. This was about 15-18' away from the trunk. LIkewise, smaller trees and shrubs were much easier afterwards to establish in the de-rooted zone. I've done it along various other trees. I only recommend taking out 1/3 of the tree's roots every few years or so. Obviously if you cut around one entirely, it would be more prone to falling over in storms or just dying.
Of course, smaller garden, nearer a house, the more impossible or risky it would be to bring in such equipment, lest you hit a buried phone/cable tv line or whatnot.

dlees,
POTS.
Ken's absolutely right.
So that's your new goal, to look for beautiful pots for your plants.
As for the privacy for the fence you are referencing, go buy some wood and put it up.
You can put a drip line into the pots too.
This way it will water your trees, and also your pots.
Just remember, pots need more frequent waterings in the heat of summer than your trees.
Your yard looks nice. Looks like you have been working on it.

and the most important thing in a pot... is not the plant.. but the MEDIA ..

and a lot of media sold is carp ...

spend some time in the container forum.. and read all about al's gritty mix .... and try to understand the concepts of what a good media does ... its more of an engineered product.. rather than some dirt to wrap around plant roots ....

ken

You are all wonderful. Thank you so much for sharing your expertise and encouragement. I know a great pot store. I'll go shopping, then start reading about how to fill them up.

Some groundcovers would be nice in addition to pots. Nature doesn't like bare soil and will fill it up with weeds at the first opportunity.
Mike