Answer: Pruning encourages new growth so now is not a good time to prune. Any new growth your shrubs develop won't be sufficiently hardened off before cold weather arrives.
Spring is the best time to prune roses and hydrangeas. Wait until buds begin to swell on the canes and stems then prune off anything that is obviously dead. You can prune both roses and hydrangeas back to about 18", pruning to an outside facing bud. Hydrangeas bloom on new shoots which develop on old wood so be sure as you're pruning them that each stem has 3-4 live buds; roses also flower on new wood but in addition to growing new stems below the pruning cut, they will also develop new canes from the center of the plant. With roses, you can prune out most of the old canes, leaving the 3-5 healthies ones.
Best wishes with your garden!
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