Why build an arbor room in the garden when all it takes is 8 trees? I would choose more comfortable furniture.
Easy to do this with 6' trees. Perhaps fruit trees, or redbuds, from Wal-Mart when they go on sale? Sooooooo much cheaper than building a wooden structure, which will never bloom. Flagstone terrace, comfy furniture and DONE.
Garden & Be Well, XO Tara
Another pic I took last January while lecturing in England.