Bare-root roses are harvested in late fall and early winter after cool weather encourages dormancy and are called "bare-root" because all the soil around their roots is removed. Depending on when it arrives, a bare-root plant will have been in cold storage for a few weeks to several months.
Follow the steps below to ensure your new roses break dormancy swiftly.
1. Remove the bush from its packaging as soon as possible after you receive it. Prune all canes that are weak, broken, crossing, thinner than a pencil, or unnecessary. Break off any bud eyes (swollen points near the union of the leaf and stem that will grow into new stems) that have elongated more than 1/2 inch during storage.
2. Prune the root tips back to white tissue to encourage new roots to develop as the wound heals.
3. Soak the plant, both roots and canes, completely under water for 12 - 24 hours to help replace moisture lost during cold storage.
4. Dig a large hole (2 by 2 by 2 feet) in a well-drained spot that receives at least 6 hours of direct sun daily during the growing season. If your soil is very alkaline, drains poorly, or cannot otherwise be easily amended, throw away all the soil and replace it with a well-drained planting mix. If your soil is healthy and strong, consider amending about half of the hole's volume with a good planting mix.
If you are replacing an established rose bush with a new one, remove all the soil and old roots completely. Then backfill with a good planting mix.
5. Shovel some of the soil mix back into the planting hole, forming a mound to about half the depth of the hole. Set the plant on top of the mound, fanning the roots out, and water well. If you live in a warm climate, adjust the plant so that the bud union (the swollen bulbous area where the rose is grafted onto the rootstock) is at soil level. If you live in a cold climate, adjust the plant so that the bud union is 2 - 6 inches below the soil level; set the bud union lower in colder regions. After the water has drained, continue filling the planting hole with soil, pressing gently around the plant roots to eliminate air pockets. Water well.
6. Following the package directions, spray the canes with an antitranspirant such as Cloud Cover or Wilt-Pruf to seal the moisture in the canes. Dehydration is the primary reason bare-root roses fail to break dormancy. As an alternative or supplement to the antitranspirant, mound a hill of loose mulch up toward the end of the canes. Spread the mound outward when the bush begins to grow.
7. Water the plant regularly, but do not fertilize until it breaks dormancy. Fertilize at a half rate thereafter, until it is growing vigorously.