Salvia officinalis aka Sage

Common sage, Salvia officinalis, is the culinary sage that most cooks know. It belongs to the mint family, Lamiaceae. Other names include garden sage and culinary sage. The plant comes from southern Europe and the Mediterranean. Its range runs from Spain and France through Italy and Switzerland to the Balkans and Greece. In the wild it grows on dry banks and stony ground, often on limestone with thin soil. It has naturalised in parts of North Africa, eastern Europe and North America.

Sage is a bushy, spreading, evergreen sub-shrub with semi-woody stems. In gardens it reaches 1.5 to 2.5 feet (0.45 to 0.75 m) tall and spreads 2 to 3 feet (0.6 to 0.9 m). Some sources record plants up to 3 feet (0.9 m) tall. It is short-lived, and older plants tend to sprawl and look straggly. Young stems are square, green and fuzzy. They turn woody in their second year. Older bark becomes gray-brown and shreddy.

The leaves are simple, opposite and ovate, with smooth edges. They are gray-green, softly hairy and wrinkled, with a clear net of veins. Each leaf grows up to about 4 inches (10 cm) long and smells strongly when brushed. In early summer, short upright spikes carry whorls of two-lipped flowers. These are bluish-lavender to pinkish-lavender and just under an inch long. Bloom falls between May and June. The green calyces stay on the stems after the petals drop. The fruit is a small black schizocarp that splits into four nutlets.

Sage needs full sun and well-drained, dry to medium soil. It copes with chalk, loam and sand, and with poor or rocky ground. Once established it tolerates drought. Wet soil, above all in winter, can kill it. In light shade the plant grows floppy. It suits USDA zones 4 to 8 and carries an RHS rating of H5. Prune in spring and trim off spent flower spikes to keep plants compact. Avoid cutting into old woody stems, as they seldom regrow. Propagate from seed in spring or softwood cuttings in early summer.

Gardeners grow sage in herb and vegetable plots, borders, cottage gardens and rock gardens. Its gray foliage contrasts well with brighter greens. Bees and butterflies visit the flowers, and deer tend to leave it alone. Several cultivars offer purple, yellow-variegated or tricolored leaves. The plant also has a long history in European herbal medicine.

Sage has few serious problems in well-drained soil. Root rot is the main risk where soil stays damp. Powdery mildew and verticillium wilt can also occur. Pests include leafhoppers, rosemary beetle, capsid bugs, spider mites, spittlebugs and slugs. Good air flow helps keep these troubles down.

Both leaves and flowers are edible. Cooks use the leaves fresh or dried to season meat, poultry stuffing, eggs and vegetables. The leaves also make an herbal tea. Eat the flowers only in small amounts. The ASPCA lists sage as non-toxic to dogs, cats and horses. However, the plant contains thujone, so large doses or long-term medicinal use can be harmful. Pregnant women and people prone to seizures should avoid medicinal amounts.