Shoots that fail to produce rose blooms are known as "blind". This is not unusual in some years, despite good cultivation of the plant, and will reduce the impact of the display.
What is rose blindness?
Rose blindness is a disorder that diverts the plant's energy so it is not able to produce rose blooms.
Symptoms
Flowering shoots develop normally, but fail to develop a terminal flower bud. Occasionally, a flower case may be form but be empty or dry.
Leaf and stem growth can appear perfectly healthy, with no sign of dieback.
Cause
The cause is unknown, but could be linked to environmental factors such as adverse
weather conditions damaging the shoot tip or the plant being grown in an excessively shady area.
Control
Where rose blindness is a problem:
- Cut a blind shoot back by half to a strong bud to stimulate further growth. This should produce flowers later in the season
- Remove a proportion of older wood to encourage new growth, leading to better flowering. This is ideally done with annual pruning, often in winter
- Improve growing conditions by feeding with a proprietary rose fertiliser and mulching
- Ensure roses are grown in a sunny, open position
Susceptible: some rose cultivars are particularly prone to this problem: 'Peace' ( a large-flowered hybrid tea rose) and 'New Dawn' (climber), which often has a poor first flush (a surge in the production of flowers) of flowers.