Russian Sage - Pruning and Maintenance
I have a Russian Sage (Perovskia) that I've had planted in a very dry,sunny bed for about 3 years. Although I am pleased with the fact that it is drought and heat tolerant, I am disappointed that it doesn't bloom very much, nor for a long time (which is what I expected). I'm wondering if I should prune it every spring, or just let it alone. Even though it is several years old, it has never gotten taller than 18", more or less. Perhaps there are different cultivars?
Please offer your experiences on growing this plant.