Tall and aromatic, Russian sage (Perovskia) is a member of the enormous mint or Labiatae family. The appearance of the plants is reminiscent of some salvias and catmint (Nepeta), to which Perovskia is closely related. The leaves are deeply dissected--almost fern-like, and the small, tubular flowers are blue-purple. Ease of care has made Perovskia atriplicifolia popular with gardeners. In recognition of that fact, the Perennial Plant Association named Russian sage its "Plant of the Year" in 1995.
Russian sage is native to dry, rocky sites in central Asia and thrives in similar conditions. It requires good drainage, so clay soil should be amended with organic matter. Alkaline soil is not a problem and neither is salt spray. Plants like Russian sage, with gray-green leaves that reflect sunlight, are happiest in sunny places and can withstand low water situations. However, as with any plant, supplemental water is necessary while young specimens establish themselves.
Pruning and Staking
Standard Russian sage varieties grow between 3 and 5 feet tall and may require staking to keep them upright. Clipping stems back by one-third early in the season will produce more compact plants. The flowers appear in the summer in most areas, and the stems persist through the winter. Cut stems back to the base at the end of winter to allow for new growth.
Good plant care starts with appropriate spacing, with mature plant size in mind. In the case of Russian sage, the plant's height would indicate positioning in the middle or even back of the border. Mature specimens can be as much as 3 to 4 feet wide, so young plants should be positioned with that in mind. Fill gaps between young Russian sage plants with annuals during the first year or two after installation.
With its loose informal profile, Russian sage is at home in cottage gardens or other informal planting schemes. It is very dramatic planted in drifts but can also complement coneflowers, rudbeckias, agastache, oenothera (winecups) and ornamental grasses. It works well in butterfly gardens, seaside landscapes and xeriscape (water sparing) layouts as well.
A number of hybrids and cultivated varieties of Perovskia are available. Some, like 'Little Spire,' have the same ferny foliage and blue-purple flowers as taller varieties but only reach about 2 feet in height. Others, like 'Longin,' are more upright, with a less spreading habit. To prolong the blooming period, check plant tags for bloom time and match early bloomers like 'Blue Mist' with later-blooming varieties.