Condea emoryi (desert lavender) ( )

A small number of shrubby wash species exhibit a drought-deciduous behavior by shedding their leaves under summer water stress. Desert lavender is a large shrub found in rocky washes and channels throughout the Sonoran Desert and lower elevation Mojave Desert up to 3,000 feet elevation, and eastward as far as the Chihuahuan Desert. This erect shrub is generally 4-10 feet in height, with simple ovate leaves covered with a dense, white pubescence. The opposite arrangement of the leaves and the sweet fragrance of the foliage help identify desert lavender as a member of the mint family. Like other drought-deciduous shrubs, desert lavender exhibit seasonal leaf dimorphism. The first leaves produced in spring are relatively large and this, with less dense pubescence. As the season progresses and water stress slowly increases, new leaves are increasingly smaller and thicker, with denser pubescence. This seasonal leaf dimorphism allows the plant to produce leaves adapted to the immediate growing conditions at the time they form. While desert lavender in California drops its leaves due to water stress in summer, it is often evergreen over its broader range in Arizona and northwestern Mexico where there is biseasonal or summer rainfall. The attractive foliage and flowers of desert lavender make it a popular plant for aridland gardening and landscaping. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."