Late winter, when plants are dormant, is a good time for many pruning tasks.
It a good time to clean up beds by cutting back ornamental grasses and perennials. Late winter is also the ideal time to prune most roses.
Usually, it is safe to prune roses in January or February, but the ideal timing really depends on the type of roses and your hardiness zone. Watch your plants grow for a season if you are not sure when to cut.
When ready to prune, you will need a few tools. Heavy-duty gardening gloves with extra- long arm shields will protect your hands from the piercing rose thorns. A pair of bypass hand pruners for small branches up to 2 inches in diameter and loppers (long-handled pruners) for thicker canes are necessary.
You need to be careful to avoid spreading plant diseases, so make sure the cutting blades on these tools are clean and sterilized. A mixture of 20% bleach and 80% water or equal parts of Lysol and water will control the spread of disease. Do not forget to sharpen these tools as needed to prevent ragged cuts.
The purpose of pruning is to open the center of each plant to allow for good circulation and plenty of sunlight. Before making the first snip, stand back, look over the bush, and decide how to shape it.
Start at the base of the rose, making cuts at a 45-degree angle. Cut about ¼ inch above outward facing buds, so new growth will grow away from, and not into, the center. Dead canes that are black, brown, or shriveled need to be replaced.
Lightly brush away any dirt covering the suckers, or new, unwanted growth coming from below the bud union. A bud union is the swollen spot, called a knot, above the roots; the rose canes grow from it. Do not disturb the roots of the rose while looking for the suckers. Cut suckers off the plant itself not just cut at ground level. These suckers steal nutrients from the bush when it begins actively growing. Also prune away any canes that are less than 2” inches in diameter and cut out branches that cross or rub against each other.
Try to leave four to six healthy canes per bush. The canes 12” to 48” high are adequate, depending on your preference or the recommended height for the type of rose.
It is not necessary to seal the pruning cuts. If cane borers are a problem, apply the cuts with white household glue to help prevent them from entering the wood.
Almost all roses will quickly grow back and recover if you make any mistakes. Just watch how your roses bloom and grow after pruning and they will show you how to best prune them next time.