What To Do With Roses in September

Our customers ask: “Should I cut my roses down in the fall?” or “What should I do with my Knockout roses now?” Some say, “My roses look terrible right now, should I fertilize them?” or “Do roses get cut down in the fall?” This post will answer these questions and others that Cape Cod gardeners have at this time of year.

1. Pruning roses in the fall. In general, we don’t prune roses in autumn for several reasons. Since pruning always stimulates growth, we don’t want to push new stems and leaves in our warm, Cape Cod fall seasons that will only get killed in early winter. Additionally, we know that woody plants (shrubs and trees) store energy in their stems that they use when they break dormancy in the spring. So it’s smart to leave those stems over the winter, and then prune when the growing season starts. The general rule of thumb is to prune roses back in the spring, when the forsythia are blooming. On Cape Cod, this is in April.
2. Fertilizing in fall? Or other soil amendments? Again, we don’t want to stimulate new growth in the warm fall season with fertilizers. So no, don’t apply fertilizer now. But put on your calendar to apply Rose-tone in early April. Soil amendments, however, are the perfect way to boost soil and rose health in the fall. We recommend applying a layer of compost such as Coast of Maine Quoddy Blend, all around the plant extending out three feet from the stem in all directions. Yes, that’s a six feet diameter circle! But knowing that every plant’s roots extend beyond the drip-line, that’s the region that has to be covered, and all of your plants in that area will be singing with pleasure.

3. My rose looks bare and ugly! If roses had blackspot fungus earlier in the season, they might have dropped all of their leaves and are now left with mostly bare stems with some new, reddish growth in the fall. At this point, leave the plant as is. Those new red leaves will continue to grow and photosynthesize into November, and they are making energy for your plant for the coming year. Plan to prune it in April, however. Cut the oldest stems down close to the ground, some of the next-oldest to 12 or 18″ tall, and then trim off the top of the remaining branches. Start spraying early in the season with an organic fungicide to help the plant fight off blackspot in the next year.

4. Should I be deadheading roses now? On Cape Cod, our roses can flower into November, so if your rose is still producing buds, by all means clip off the spent flowers once the petals have fallen. This promotes new growth.

5. Okay…I’m deadheading, and adding a layer of compost around my roses in September. What else should I be doing for roses in the fall? Enjoy them! Appreciate these plants that have been performing from June into September. Cut the flowers and add them to small bouquets. Savor their beauty as we go from summer into fall.