Climbing roses bloom on new stems that grow on old wood. Pruning them back in late winter will encourage new, flowering stems. If you do not prune, most of the new growth will be at the ends of the main canes instead of lateral stems that produce flowers. Roses need two things for blooms: sun and nutrients. Nitrogen, phosphorous and potassium are the 3 major nutrients for all plants. (They correspond to the 3 numbers on fertilizer packages.) Nitrogen promotes growth of green leaves. Phosphorous is essential for blooms. Roses are heavy feeders during their bloom period. The second and third numbers on the package should be higher than the first. (Avoid feeding with high-nitrogen fertilizer - it will encourage foliage growth at the expense of flowers.) Keep your roses consistently moist and mulch with 2-3 inches of compost to help maintain soil moisture. Rosarians I know fertilize their roses every 6 weeks during the blooming season. Prune your roses in February or March and by next summer your climbers will have enough old wood to produce new flowering stems and you should have lots of blooms. |