Jerusalem sage's show blossoms are suitable for cutting and arranging and their sweet nectar is a favorite of many species of butterflies.
Jerusalem sage is a bushy sub-shrub that grows in a mound up to 3 ft (1 m) high and 5 ft (1.5 m) across. It is closely related to, and looks a lot like, the common sage of gardens, Salvia officinalis. Like most members of the mint family, Jerusalem sage has square stems and opposite leaves. The much branched stems are fuzzy and can become woody, especially near their bases. The aromatic grayish green leaves are elliptic, 2-4 in (5-10 cm) long, and densely white-wooly on their undersides. Whorls of 14-36 butter yellow flowers, each about an inch (2.5 cm) long, grow in tiers on erect stems above the foliage. Typical mint family flowers, they are bilaterally symmetrical with a prominent upper lip shaped like a hood and curled over the lower lip.
Phlomis fruticosa ‘Miss Grace’ is a little larger plant with larger leaves and larger flowers than the typical species. Phlomis ‘Edward Bowles’, also larger and more robust, is believed to be a hybrid between Jerusalem sage and P. russeliana, a related species from Syria.
Location Phlomis fruticosa grows naturally in dry, rocky areas in the eastern Mediterranean region, especially Turkey, Syria and Greece.
Culture Light: Grow this evergreen mint in full sun up north and partial shade in hotter climates. Moisture: Jerusalem sage needs a well drained soil. Established plants are quite tolerant of drought. Plants are more susceptible to cold in damp soils. This densely pubescent shrub should be grown in an exposed position so that the foliage can dry quickly after rain. Hardiness: USDA Zones 7-10. In Zone 7 Jerusalem sage dies to the ground in winter, but usually returns in spring. The plant often remains evergreen (shall we say evergray?) in zones 8 and above. Propagation:Soft wood cuttings from non flowering shoots taken in spring or summer can be rooted. For best results insert cuttings in sand and mist them several times a day. Roots should develop in a couple weeks or less.
Jerusalem sage makes a beautiful addition to herb and informal gardens where its fuzzy gray foliage provides interest even when the showy flowers are not present.
Jerusalem sage is grown in borders and as specimen shrubs alone or in groupings. The velvety gray-green foliage and unusual looking, yet strikingly beautiful, yellow flowers go well with blue, red and orange flowered plants. These are rather coarse looking bushes, especially useful for informal gardens. Jerusalem sage does well in poor, sandy, even rocky, soils. It is tolerant of salt and apparently unpalatable to deer. It tolerates strong pruning and should be trimmed before flowering in spring to maintain a compact shape. The flowering stems make interesting cut flowers, and are easily dried for everlasting arrangements. Cutting the stems off right after blooming will encourage subsequent blooming later in the same season.
Jerusalem sage seems to be more popular in English gardens where children have been known to pull off the flowers and suck out the sweet nectar. Bees and butterflies like the nectar too, and birds will eat the seeds if you leave the spent flower stalks through the winter.
The mint family, Lamiaceae (or Labiatae if you prefer), includes some 5600 species in 221 genera. There are about 100 species in the genus Phlomis.