Phlomis is a genus of herbaceous plants and shrubs in the Lamiaceae family. The 100 species in this genus are native to northern Africa, eastern and central Asia, and Europe. The plants have been naturalized and can now be found throughout the world. Phlomis is a very distinctive plant that some would say looks curiously strange. Gardeners who enjoy unique bedding plants tend to like shrubs in this genus. Beginning gardeners usually have success growing this particular plant because it takes very little maintenance.
Also known as lampwick plant, Jerusalem sage, and Turkish sage, the plant grows best in U.S. Department of Agriculture Hardiness Zones 7-11. This means that the lowest temperature it will tolerate is 0° Fahrenheit (-17.7° Celsius). Plants in this genus prefer full sun exposure. They also prefer soil with some sand or clay with a pH level of 6.1-7.8, which is mildly acidic to mildly alkaline. They need an average amount of water, but do not mind if the soil is on the dry side. The plant does not like to be in soggy or muddy soil.
Generally, species in this genus range from 4 to 6 feet tall (1.2-1.8 m) and are about 5 feet (1.5 m) wide. Some cultivars, such as Edward Bowles, are considerably smaller, with an average height between 1 and 3 feet (0.5-0.9 m). From late spring through early fall, Phlomis blooms with very distinctive, hooded, whorls of bright yellow flowers, that surround straight hairy stems. The 6 inch (15.2 cm) foliage is greenish-gray or silvery and has a wrinkled, velvety texture.
These plants make fine borders for flower gardens and English gardens, or several plants can be grown together near a warm wall for a dramatic effect. Rock gardens or containers also make good homes for these plants. Bees, birds, and butterflies are all attracted to gardens where Phlomis is planted. All of the species in this genus are tolerant of heat, humidity, and drought. They are also resistant to deer.
Phlomis can be propagated by splitting the root ball, taking a cutting from the soft wood, or by seed. Seed can be started inside prior to the last frost of the season; it cannot be sown directly into the ground. The seeds will germinate in two to seven weeks, so should be started in January to be ready for spring transplanting.
Leafhoppers are the primary pests that enjoy nibbling Phlomis. The leafhoppers can be removed by hand or with insecticidal soap. Phlomis is, however, resistant to most common plant diseases. Those who want an easy-to-care for, interesting plant for their gardens may want to consider adding a species of Phlomis.