Ten Mistakes in Pruning Roses

by Baxter Williams

Houston Rose Society

  1. Wrong time. Best time for “pruning” (deep cuts into a bush) is the coldest, wettest day of the year. For us that means mid-February = Valentine’s Day. After these deep cuts, just “groom” bushes.
  2. Wrong tools. NEVER use anvil-type shears. ALWAYS use bypass shears (where blades pass), wear leather gloves and use sun-screen to protect your skin.
  3. Wrong stem size. “If it is smaller than a pencil, cut it off.” The stem’s next growth at that place will be that same diameter. Think what stem size you wish to have. A large bloom needs strong stem support.
  4. Shears held wrongly. Blades on bypass shears are two sizes, one very thin and sharp, the other thick curved. Place thick blade against the piece to be cut away. It will bruise the stem piece it touches. You want it to bruise the piece cut off.
  5. Wrong place on the stem. Cut about 1/8-inch above where a leaf is (or was) attached. The old advice to “make the cut at 1/4-inch and a 45-degree angle” is mostly untrue. A 1/8-inch cut gives better results. Leaving a longer stem piece will likely cause stem die back to the leaf (or lower). Not good. Don’t leave a piece likely to die.
  6. Wrong angle of cut. Any angle near 45-degrees is OK. A rakish, smaller angle cut is very bad. A totally horizontal cut is also OK. A sloped cut is supposed prevent rot from water sitting on cut end. But in that case: a. the water would soak in (plants would like that!), or b. it would evaporate away. Water would have to sit for weeks before the stem would rot. Not going to happen.
  7. Wrong, or no, post-cut care. In general, no post-cut stem treatment is required. If something does go wrong at the site, trim the stem a down little farther. If you are cutting an old stem at the bud union (big knot with all of the stems emanating from it), seal the cut. DO NOT USE BLACK TREE PRUNING PAINT! It will burn the stem’s cambium layer. Use white glue.
  8. Fail to protect the bush after pruning. It is INCORRECT to assume a bush is safe from disease. Blackspot fungus, the bane of rose growers, over-winters on stems, whether there are leaves or not. Protect plants immediately after pruning to prevent future defoliation, particularly if neighbors’ roses are infected with blackspot.
  9. Feed the bush too soon, or too much. Roses are dormant (not growing) in mid-February. As soon as the soil begins to warm up, roses need “to eat.” Moderate feeding with a balanced rose food will be in order, with a repeat feeding in about 4 weeks. Too much food overly stresss the plant, causing defoliation.
  10. Try to do it alone. While you likely can prune a bush without help, it might be advisable to seek out advice from a Consulting Rosarian. That person is trained to prune and is experienced in techniques. Contact the Houston Rose Society at www.houstonrose.org for help.