Common garden sage is a perennial ornamental herb, which may grow to approximately 90cm. The leaves are velvet green-grey and add a nice delicate appeal to a garden border. The 5-7 cm leaves are set in pairs along the stem. The flowers are a blue-purple and have a tube-like appearance. All the parts of the plant are fragrant with a strong scented odour and a bitter, astringent taste.
The natural habitat of Salvia is the dry, arid regions of the Mediterranean and Northern Africa, and some areas of the United States and South America. Salvia varieties require a lot of sun, and are ideally suited to Australian conditions. They are generally well adapted to harsh, dry and rocky environments.
Common sage flowers for three to four weeks, after which the flower stems need pruning. After about three years, the plant may get very straggly or woody and needs to be replaced. It is successfully propagated by cuttings, although an attempt can be made with seed. Some care is needed with young plants to allow them time to become established.
Salvia varieties, including common sage, do well in a wide range of soil types and garden conditions. Poor soil may be improved by adding organic matter and mulch will help to retain water in hot conditions. Sage is adapted to dry conditions and requires a well drained soil, so that the roots do not become water logged.
Salvia varieties also do well as container plants and should be planted into pots that will be suitable for the fully grown plant. The soil mix should be coarse, with extra perlite and organic fertiliser mixed through. Liquid organic fertiliser may also be used throughout the growing season.
Annual varieties may be grown together in a large container and discarded at the end of the growing season. Perennial varieties may also be discarded, if you intend to replant the following season or pruned after flowering and left over winter. In cooler regions, the plants may need some protection over winter. Longer growing, hardy varieties may be re-potted each year, in pots suitable for their size.