Before taking shears in hand, understand what your goals are.  Pruning roses has a multitude of rewards, including healthier plants, stronger growth and flowering, elimination of diseased or damaged canes, and improved overall appearance.  Pruning stimulates growth, leading to robust plants.

Do not be overly concerned about making grave mistakes; even overly hard pruning is more beneficial to the plant than no pruning at all.  There is definitely room for error when pruning, and as you go, you’ll accumulate more and more insight into what roses like and don’t like.

There are three primary seasons for pruning, late fall (early winter), early spring (late winter), and during the growing season.  Each season has a specific goal for which we prune.

Late Fall (Early Winter) Pruning
In general, it is not absolutely necessary to prune in late fall.   The reason to prune during this time period is to protect the plant from winter damage, chiefly due to long canes whipping in the wind and disturbing the root structure.   Further, many gardeners like to tidy up their garden with a bit of light pruning.   Generally, fall pruning is not hard pruning, just taking off some of the taller growth from the preceding season.  Finally, in winters where the temperatures fall below 10 degrees Fahrenheit, do not prune in late fall.

If you choose to prune in late fall, be careful about your timing.  Pruning stimulates growth, and there is very real danger of pruning too early in the fall, stimulating new growth which is hit hard during the next hard frost.  If you choose to prune your roses in fall, make sure that the plants are fully dormant and you are past the time period when extended warm spells could cause the plant to reawaken.  In general, wait until several hard frosts have occurred, and foliage is brown.

 During fall you may notice the canes of your roses turning from green to rusty brown.  This is a natural hardening off as the rose prepares to go dormant for the winter.