Marcus Sage has masses of beautiful spikes of royal blue flowers rising above the foliage from late spring to early summer, which are most effective when planted in groupings. The flowers are excellent for cutting. Its fragrant narrow leaves remain grayish green in colour throughout the season. The fruit is not ornamentally significant.
Marcus Sage is an herbaceous perennial with an upright spreading habit of growth. Its relatively fine texture sets it apart from other garden plants with less refined foliage.