Most heavy pruning of roses is done during the dormant season, and we are pruning for health, shape, vigor and superior flowers when we do so.
Some pruning however does need to be done during the growing season but our goals at this time of year are different.
Pruning in the spring or summer usually is done to shape the rose, or if it is a rose that will continuously flower, deadheading, or the removing of old flowers needs to be done in order to encourage the rose to reflower.
Deadheading repeat-flowering roses has multiple benefits. Not only will it conserve plant energy and produce more flowers, but it will also remove hiding places and food for insects which often become pests in our garden. It may even permit minor improvements in air circulation, thus reducing the potential for fungal diseases like powdery mildew and leaf spot.
Basically we deadhead to remove old and dead flowers from a rose bush so that the hips, the rose fruit, do not form. By diverting the energy normally used for hip development, we give the plant more energy to produce new flowers and cane growth.
The only reasons for deadheading a one-time-blooming rose are to give the plant a cleaner appearance and to maximize vegetative growth.
Deadheading should vary between types of roses.
To deadhead Hybrid Teas and Floribundas: Remove a spent flower and the cane beneath it back to the first outward-facing leaf with five leaflets. Deadheading back to a leaf with fewer leaflets often results in non-flowering new growth, called “blind wood.”
To deadhead repeat-flowering roses: Like shrub roses or climbers, this can be more variable. New flowering wood can be produced from a bud at the bract beneath a flower or from buds at any leaf axis.
On these roses, it is better to deadhead back to the bract beneath the flower, and observe whether new flowering wood grows from this point. If flowers are not produced, prune back to the first leaf and start the observation process again.
Continue deadheading back to the highest leaf on a cane until you know the pattern or growth and bloom for a cultivar.
This might not be as clear cut as what to do for Hybrid Teas or Floribundas, but this will really become helpful when you have deadheaded your roses for a season and know what is best for them.
Then every season thereafter you will get the best flowers from your roses.
Hilary A. Rinaldi has been in the landscape industry professionally for over 20 years and is a Certified Organic Grower. After a stint on TV as “The Weekend Gardener,”she started her own Web magazine in 2000. Visit her site here.