Question
QUESTION: Hi,

I live just outside Manchester (UK) and we have a climbing rose that is very overgrown, so much so we are now having trouble opening the windows. When and how hard should I cut it back (it is at least 25 years old).

ANSWER: Climbers usually respond very well to being pruned back. However because it is an old one caution is best when deciding how much to cut. When you cut look to see where the lowest of the new canes are coming from and don't cut below them. Cutting below them could mean the rose can't push out any new canes because the bark is too thick. Spring is always the best time to cut a rose back and spring is when the rose has a more vigorous start to growing. I would cut it back by a third for next year and then another third if need be the next spring. Right now you could always tidy it up by cutting it back a little to say around 2 feet. But the problem is that it will probably get even with you and grow back during the summer.

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QUESTION: Can you just clarify, when you say "cut it back by a third for next year", when do I do that (now or after the summer (Oct, Nov or Dec)). I'll be honest I do 'trim' it back in Dec, so I can trail christmas lights in it but I'm not sure that is the right time (my wife thinks it's the wrong time). I have cut it back in the past and it does get 'even' :-))!

Answer
There are three times of the year that gardeners prune back roses. The main one is in the early spring as the rose puts out a greatest amount of vigour at that time. So cutting your climber back by a third in the spring is the best time if the pruning might put it under shock or stress. It will have the extra amount of strength to cope with the cutting.
The next time to prune is in the summer and this is done to keep a rose under control such as extra long canes or growing in the wrong directions. You could, if you wanted to, cut back any long canes that are going to add to the height. Sometimes though the rose , if it is a vigorous one, will simply produce the amount that was cut off back again.
The last is in the late autumn and this is usually done to stop the winter winds waving tall canes about and breaking them, also some gardeners prune their roses in the fall  and  not in the spring because they  get a mild winter.
Again I would go easy because the rose  may have to go through a nasty winter and the cuts will not be sealed. Because your rose is an old one, it is better to cut 2 feet off in the spring, tidy up in the summer, leave alone in the fall and then cut it back where you want to again the next spring. This will ensure the rose won't croak on you. I speak with authority as I am old too!!