I am new to zone 5 but have been doing a lot of research about the same. In Florida, we had crepe myrtles that could be pruned into just such a shape. The closest thing I think I've found is an Amelanchier. You can get them with multiple stems and then prune them up. Some have great Fall color. But, they are deciduous. Oh....I just looked. They do make berries, so maybe that's not a good idea for you. Nice plant though.

How about a wisteria standard? Keep in mind what ever standard you chose will like a tree make a fair amount of shade for the plants below it, under my wisteria I have hellebore growing happily. kt

Here is a link that might be useful: White Flower Farm

Thank you both for your suggestiongs. The wisteria is gorgeous! And I just bought some hellebore - a new plant for me! I fear that in my location the wisteria would grow "into" the porch since the top flattens/spreads out. I looked up the amelanchier. There is a small one called Prince William and a prettier (I think) but larger one called Princess Diana. They are very slow growers. yes, they have berries but they are edible and tasty, if I could beat the birds to them. I also found a purple leaf sand cherry that is multi-stemmed and could be limbed up. Any experience with those?

Have you thought of a climbing rose on a trellis instead of a flowering shrub? I have Zephirine Drouhin roses to add some privacy to my covered porch.

When this photo was taken, the roses were climbing on the railing and post - since then I've put trellises up so the coverage will be more even.

Claire

Wow - beautiful. No, I hadn't thought of that. I would need rather high trellises. But maybe "my" carpenter could build something that is high and is supported at the roof line. This would also block some of the intense afternoon sun. A very good idea which I will ponder.

Another vine would be clematis, though it might take a year or three to provide good coverage. If you bought a large one (silver star vinery is a good source of big healthy clematis without a huge price) it would fill in faster. You could grow it up a trellis on the porch or a free-standing obelisk/tuteur. Annual vines, such as scarlet runner beans or black-eyed susan vines running up a net, wire mesh, or strings might provide good seasonal coverage until whatever you decide for your permanent solution gets big enough. Even the trellis itself can provide some screening.

If you are looking for privacy when deciduous plants have lost their leaves there are some narrow evergreens (not flowering, I know) that you might want to consider as an addition. Do a search for columnar evergreens.

Look into some of the hardy hydrangeas. I've seen some of the varieties of H. paniculata, which will be fully hardy for you, pruned into tree forms. If you use the search function in this forum, there are a couple of old threads on hydrangeas which have several images of various H. paniculata varieties. Some of the varieties include Limelight, Pinky Winky, Tardiva, Kyushu, and The Swan. Be sure to check width, since they are not all the same size.

Here is a link that might be useful: Silver Star Vinery