The latest you can handle transplant rose bush timing is mid-October to early November in most areas. You need to move your rose at least 4-6 weeks before the ground freezes solid. This gives roots time to settle in before winter dormancy sets in.
Knowing moving roses when makes all the difference in survival. I moved a climbing rose in late October three years ago. The plant looked stressed for a few days but bounced back fast. By spring, you couldn't tell it had ever been moved at all.
In my experience, fall works better than spring for moving roses. The cool air keeps the top of the plant calm while the still-warm soil lets roots grow. Your rose focuses all its energy on root growth rather than pushing out leaves and flowers.
Portland Nursery says mid-October through early November works best. They also say to cut your rose back to about 18 inches before you move it. This reduces stress by giving the plant fewer leaves to support while roots recover.
Late season rose transplanting carries more risk the longer you wait. If roots don't get enough time to grow before freeze, your rose may not survive winter. A rose moved in November with only two weeks before freeze has poor odds of making it through.
Dig your new hole before you dig up your rose. Make it twice as wide as the root ball you expect to get. This way your rose spends minimal time out of the ground. The less time exposed to air, the less stress on those tender roots.
When you dig the rose, keep as much of the root ball intact as you can. Start digging about 12 inches out from the main stems. Go down at least 15 inches to get most of the roots. Wrap the root ball in burlap to hold it together during the move.
Water your transplanted rose deeply right after planting in its new spot. Add 3-4 inches of mulch around the base to keep soil warm longer. Don't fertilize until spring since you want the plant to focus on roots, not new top growth.
Watch for signs of success the following spring. New leaf buds swelling on the canes mean your rose made it through winter with healthy roots. Growth may be slower the first year as roots rebuild, but your rose should bloom normally by summer.
Read the full article: When to Plant Roses for Beautiful Blooms
