If a rose was classified before 1867, it falls into a class known as old garden roses. There are a dozen major groups of old garden roses and several lesser known. As a group, old garden roses don't require heavy pruning and some, such as damask, may be harmed by it. Old garden roses that bloom once should be pruned right after blooming, and only lightly. Repeat bloomers can be trimmed heavily. Don't prune any garden rose that is under 3 years old, the experts at the Santa Clarita Rose Society caution.
Pour 1 cup of Lysol disinfectant and 4 cups of water into the bucket and stir until it's mixed. Dip the pruning shears into the solution between cuts.
Remove twiggy and thin growth (less than the diameter of a pencil) by cutting the stems back to their points of origin. Check the interior of the plant for this type of growth. Its removal will allow better air circulation within the rose plant. Look for branches that are crossing over others and cut these off as well.
Prune off damaged, dead and old canes. Older rose canes have a rougher exterior than new canes and are generally gray and have white thorns. Remove these to the closest main branch.
Cut back the repeat bloomers, up to 1/3 their size. Some classes, such as the Gallica, can be cut back to just a few inches off the ground and come back healthy the following season.
Prune diseased canes last and bag them as soon as they are removed.
Rake the rose bed after pruning, and bag up all foliage, twigs and other debris.
Water the old rose bush until the water puddles. When it drains, add a 3-inch layer of mulch, 2 inches from the main cane, spread in a 1-foot diameter around the plant.