Answer: A good rule of thumb in planting roses is to take into consideration the type of rose, and the length of growing season. Climbers require more space than shrub roses, but short growing seasons mean the plants won't have time to put on a great deal of new stems and foliage before season's end. Your new climbing roses can go as close as 3' for quick coverage, or as far apart as 6' if they're in a protected area and will grow over a long summer season.
Planting 18"-24" away from a supporting trellis or wall should provide adequate air circulation for the canes and prevent reflected heat from damaging the foliage.
Hope your new roses bloom prolifically for you!
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