Another favourite – Salvia ‘Indigo Spires’. This beauty grows as tall as 1.7m in my garden, though it’s supposed to be 1.2m (do nurseries deliberately understate plant sizes so as not to disappoint?). I think I bought three plants to start with, but I’ve since taken cuttings and spread them around the garden. Four to six plants, 40-50cm apart, will grow a big clump of deep blue spikes on a mound of lush mid-green foliage.
I cut the old stems to the ground in winter; by then the new stems are already forming and by spring there’s a decent amount of foliage, so it never leaves a totally bare spot. The plants flower right through summer, then I trim off the dry flower stems after the heat of February, and they flower again all through autumn – they’re still going gangbusters in my garden in late May. The blue stems and calyxes look gorgeous even after the petals fall. The bees are mad for them, and they make a great, blowsy bunch of cut flowers.