From the ArcaMax Publishing, Gardening Newsletter:
http://www.arcamax.com/news/gardening/s-156755-432570
Question: I have an old-fashoned climbing rose that has likely been
growing in my yard since before I was born. It is very vigorous and
has huge canes at the base. I am not sure of the variety, but it is a
very pale pink with a nice fragrance. I understand that many old rose
varieties will rebloom in the fall -- in addition to their usual
spring or early summer bloom period. Is there anything I can do to
encourage mine to bloom twice? I have been deadheading; should I also
be pruning in any special way?
Answer: There are several types of climbing roses with various bloom
patterns. Some older types of climbing roses -- the "ramblers" --
produce a profusion of relatively small blooms all at once, usually
starting in early summer. This show might last amonth or so, then
blooming is over for the season. Another group of roses is the
large-flowered climbers. These generally have flowers over 2" in
diameter, and bloom for a longer period but much less profusely than
the ramblers. Some varieties of large-flowered climbers bloom
continuously over the growing season; others bloom once in early
summer and have a second flowering later in the season. There are also
climbing hybrid teas, climbing floribundas, and pillar roses.
Generally, genetics determines whether a rose bush will bloom just
once or will repeat bloom in the fall. Removing hips will help
encourage a repeat bloomer to put more energy into the second bloom,
but it won't force a one-time bloomer to put out more flowers. Keep
your bush adequately pruned and fertilized, and it will fall into its
natural blooming pattern.