Tightly packed clusters of lilac-purple flowers on tall, stiff, branching stems from June to September.
This stylish perennial has been enjoying a resurgence of interest in recent years.
Perfect for a sheltered, sunny, well-drained spot, its open, transparent shape means that it can easily be used at the front or middle of the border despite its height.
Grows up to 5 ft high
Loved by bees and butterflies