I have a mature climbing rose. It's about 5 years old, so I think it has probably reached its maximum size. It's a little over 6 feet (~2 meters) high and about 2 feet (.6 meters) at its widest point.
I'd like to plant a young rose of the same basic variety next to it, as close as possible. The preferred spot is to the right of the current one as you look at it, in the space before the fence post, which is about a foot away from the widest part of the existing plant. The leaves and flowers can spread as far as that fence post, or a few inches beyond, but the base must end at or before it.
Would that be too close? If so, what's the minimum amount of space I should leave between them? I don't mind if the foliage overlaps. In fact, I'd prefer it that way. I'm just concerned about crowded root space, especially for the younger one, which I haven't purchased yet, but is about 1½ feet (.5 meters) tall, and still quite narrow at the base.
Unfortunately, I don't know the variety of this rose, so I'm hoping the pictures will help. I'd have to go back to the store to check the variety of the new one. I didn't want to buy it without getting some advice, and since it's at a department store, rather than a nursery, I couldn't find someone with good knowledge of its growth habit. Actually, I'd love to cover more of that ugly fence, but assume that means a bushier plant with a bigger root ball, which I didn't think would fit.
Kevinsky's answer made me wonder if the companion plant really has to be a rose at all. I'm open to something else, if it meets the criteria.
The pictures are from before it's in full bloom. It's usually prettier than this, with lots of flowers all the way to the top!! (Yes, I'm aware of the holes in the leaves! I thought I should either ask about those separately, or do some research on the site, where I'm sure I'll find some good diagnostic and treatment information.)