Thank you all so much. Arturo,what you write rings so true for me, too. The place I'm planning on putting them is on a slope,too, at the top of my hill-garden, so air circulation shouldn't be a problem at all. My idea is, in fact, to espallier Quicksilver at the top of the slope,and then put ET below it; i.e.,lower down on the slope.
People seem to automatically think that in a warm climate all plants always grow larger than they do in colder climates, but that just isn't true. SOME certainly do. I got this rambler called Louis Mon Ami from a nursery in the Netherlands,which stated that it grows to be 3-4 meters tall,and that you could "use it like a clematis". HA! mine is a total monster,more than double that size,sprawling all over, wishing it had a house to eat. But less vigourous roses are a totally different story; I think they suffer from the excessive heat and drought of the summer, so here, instead of "winter die-back", we get "summer die-back". So the spacing question is not easily answered.
