These plants are subshrubs originating from Afghanistan with an upright habit and grey-white stems and silver-grey leaves. They create a wonderful ornamental effect if grown singly, as a clump, or as edging to the front of a border.
The flower spikes grow up to 4ft in height and have tubular violet-blue flowers in 12in panicles. These appear profusely in midsummer and on into early autumn. The sheer vigour and floriferousness of this plant makes it a great favourite with our customers.
We do not usually provide plant supports for P. ‘Blue Spire’ as its flower spikes are usually resilient enough to stand up on their own. On very rich soils or more windy locations this may not be the case.
The key thing to remember when dealing with this easily grown plant is that it needs to be cut down nearly to ground level in the autumn to encourage vigorous new growth and flowering shoots in the following season.
P. ‘Blue Spire’ will grow in any moderately fertile soil in full sun. It will tolerate chalky soils and thrives in coastal locations. Propagation is straightforward from softwood cuttings in late spring.
