I love the unusual nature of this 'Turkish Sage'. I used to covet it in my neighbours garden until I plucked up the courage to ask what it was.
The yellow flowers on this herbaceous perennial bloom at intervals along the the spike and the green/grey foliage is large enough to nice, but not so big that it is dominant.
Place her in full sun and you will enjoy and show off these wonderful flowers all summer. The seed heads are also interesting so don't be too quick to cut back in autumn!