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Products > Rosmarinus officinalis Irene ['Renzels']   Rosmarinus officinalis Irene ['Renzels'] - Trailing Blue Rosemary       Habit and Cultural Information Category: Shrub Family: Lamiaceae (Labiatae) (Mints) Origin: Mediterranean (Europe) Evergreen: Yes Flower Color: Blue Violet Bloomtime: Winter/Spring Fragrant Flowers: Yes Synonyms: [Salvia rosmarinus] Height: 2-3 feet Width: 6-8 feet Exposure: Full Sun Seaside: Yes Summer Dry: Yes Deer Tolerant: Yes Irrigation (H2O Info): Low Water Needs Winter Hardiness: 15-20° F Rosmarinus officinalis Irene ['Renzels'] - (Trailing Blue Rosemary) - A semi-prostrate spreading evergreen shrub to 2 to 3 feet tall by 6-8 feet wide with bright green foliage and blue-violet flowers in late winter through early spring with sporadic bloom year-round. This prostrate rosemary has been touted as a breakthrough in rosemary's because of its brilliant blue-violet floral color and greener foliage. Cascades beautifully over walls with a hummocky growth habit. Plant in full sun. As with other Rosemary it is resistant to deer and rabbit predation, tolerant to salt spray, alkaline soils and drought. Hardy to 15°F. This plant was discovered in 1991 by Phil Johnson who found it growing in the crack of a dry stack retaining wall he had built in 1984 in the garden of a client in Orinda, Calif. Phil named the plant for his Black Labrador Princess Irene, who was also known as Renzels, using 'Renzels' as the patented cultivar name and Irene as a marketing name. In May 2, 1995 is was granted US Plant Patent PP9,124, which expired in April 2014. We were first licensed to grow this plant in 1996 and will continue to grow this very nice rosemary cultivar, though it is no longer protected by a patent. When we first grew this plant it was thought to be a low ground hugging groundcover variety but in time have noted it getting taller - still very nice as a groundcover but not as low as some others such as the paler blue flowered Rosmarinus 'Lockwood de Forest'. Recent DNA analysis now shows the genus Rosmarinus to be fit squarely into the massive Salvia genus, which already has about 1,000 species. Since the specific epithet "officinalis" is already used in the genus Salvia, the new name for our common rosemary is now officially Salvia rosmarinus. Joining Rosmarinus in this move to Salvia is Perovskia and the little know genera Dorystaechas, Meriandra and Zhumeria. This change was published in an article by University of Nebraska biologist Bryan T. Drew, Jesús González-Gallegos, Chun-Lei Xiang, Ricardo Kriebel, Chloe Drummond, Jay Walker and Kenneth Sytsma titled "Salvia united: The greatest good for the greatest number" in the February 2017 issue of Taxon 66(1):133-145. For the sake of our customers and ourselves, we continue to list the Rosemary in the genus Rosmarinus!  The information about Rosmarinus officinalis Irene ['Renzels'] displayed on this page is based on research conducted in our nursery library and from online sources we consider reliable. We will also relate those observations made of this plant as it grows in our nursery gardens and in other gardens that we have visited, as well how the crops have performed in containers in our nursery field. We will also incorporate comments we receive from others and welcome hearing from anyone who has additional information, particularly when they share cultural information that would aid others in growing it.     [MORE INFO]