Jerusalem Sage, or Phlomis fruticosa, is native to the Mediterranean region, specifically found in countries like Greece, Turkey, Cyprus, and parts of Italy. It thrives in the Mediterranean scrubland, on rocky hillsides, and along the coasts where it benefits from the region’s climate – hot, dry summers, and mild, wet winters. This environment has shaped its adaptation to drought and well-drained, often poor soils.
Phlomis fruticosa has been appreciated since ancient times, with its genus name “Phlomis” derived from the Greek word for “flame,” possibly due to its bright yellow flowers or its traditional use as a wick for oil lamps. Historically, it was also used for medicinal purposes in the Mediterranean, where various parts of the plant were believed to have healing properties, especially for wound healing and digestive issues. Its ornamental value was recognized in Europe during the Renaissance, leading to its cultivation in gardens, particularly for its ability to attract pollinators like bees and butterflies. Over time, it has become valued in both formal and informal garden designs for its hardy, structural form and vibrant blooms.
Use it in an herb garden as an accent, in raised planters or containers, or in vegetable gardens. The flower heads and seeds can be dried and used in flower arrangements. Jerusalem sage looks nice when combined with Salvia greggi, Salvia leucantha, and Salvia clevelandii.
Characteristics
- Foliage: The leaves of Jerusalem Sage are large, ovate, and have a wrinkled, grey-green appearance with soft hairs, giving them a velvety texture. They are aromatic when crushed, releasing a scent reminiscent of sage.
- Flowers: It’s known for its striking, tubular, bright yellow flowers that appear in whorls around the stems, creating a tiered effect. Each flower spike can bear up to 20 flowers, blooming from late spring to early fall, providing a long season of color.
- Growth Habit: An evergreen shrub in warmer climates, it forms a dense, mounding habit that can reach about 3 to 4 feet in height and spread. In colder areas, it might act as a semi-evergreen or even die back to the ground in winter, regrowing from the roots in spring.
- Drought Tolerance: Highly drought-resistant once established, reflecting its Mediterranean origins. Its deep root system helps it access water in dry conditions.
USDA Zones
Jerusalem Sage is hardy in USDA Zones 7-10. In Zones 7 and 8, it may lose some leaves or die back in winter but will return in spring. It’s fully evergreen in zones 9 and 10, where it thrives year-round.
Cultivation
- Light: Prefers full sun but can tolerate some light shade, especially in hotter climates where afternoon shade can protect it from excessive heat. It blooms best in sunny locations.
- Watering: Once established, it’s quite drought-tolerant. Water young plants regularly until they’re established, then reduce frequency. Avoid overwatering, as this can lead to root rot.
- Soil: Adaptable to various soil types but prefers well-drained, even poor, sandy, or rocky soils. Good drainage is crucial to prevent root rot.
- Temperature: Thrives in warm conditions but can handle some frost in its hardier zones. In colder zones, mulch around the base in winter for added protection.
- Pruning: Prune after flowering to maintain shape, encourage new growth, and potentially stimulate a second bloom. Deadheading can also promote more flowers, but leave some for seed if you want natural spread.
- Propagation: Can be propagated by seed, but more commonly by softwood cuttings in late spring or early summer or by division in spring. Seeds need stratification (cold treatment) to germinate well.
- Pests and Diseases: Generally resistant, but watch for aphids or fungal issues in overly wet conditions. Good air circulation and avoiding over-watering help prevent problems.
- Fertilization: Requires little; an annual application of compost or a balanced, slow-release fertilizer in spring is usually sufficient.
- Cultivation Tips: Its structure makes it excellent for Mediterranean-style gardens, borders, or as a specimen plant where its architectural form can be appreciated. It’s also great for attracting pollinators, contributing to garden biodiversity.