Answer: The best time to do that would be right after the main flush of bloom in the spring. She could also cut it back as hard as she needs to in very early spring, but that would cut off a lot of the main spring blooming for next year. Once she has cut it back hard, she can then periodically tip prune to encourage it to branch and stay full and a bit smaller than normal. One of the "benefits" to growing this type of rose is that it does not require a lot of pruning, so it is a shame to have to do all that work. It is also potentially a large plant so she might be happier using a smaller maturing variety of rose in that location instead.
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