Let me introduce you to the camel of the plant world, caudiciform succulents. I`m not comparing this plant to a camel because it has one hump or two, but because of its specialized stem, called a caudex, which can store an amazing amount of water, allowing the plant to survive in arid climes. The caudex, essentially an enlarged, trunk-like stalk, can take on strange, often amorphous shapes in pursuit of long-term water storage.
The Desert Rose (Adenium obesum), one of the more common caudiciforms in cultivation, is native to arid areas of Africa. Related to the oleander, its sap is poisonous and has been used to coat arrow tips for hunting. Though they are not everyone`s ideal of beauty, they can be harder to locate and more expensive than many other exotic plants. Prior to the 1960s there were few in cultivation.
The stem (caudex) of the Desert Rose is as plump as a turnip and silvery in color to reflect the sunlight. Slender branches emerge from the top of this swollen stem and are topped with small oval leaves. Gorgeous flowers in shades from deep red to pure white burst forth for many weeks during the spring and summer. Some of the improved cultivars will bloom almost continuously during their growing season if given proper care.
Many caudiciforms are deciduous and are in leaf for only part of the year. When they are actively growing, they should be watered thoroughly and fertilized, almost like a tropical plant. It is imperative the soil drain well. During its dormant period, the Desert Rose should be treated like a cactus with only light, occasional waterings, after which the soil should be allowed to dry to avoid root rot.
To ensure good drainage, try a cactus mix comprised of at least 50 to 75 percent drainage material, such as scoria (volcanic rock), gravel or perlite. Grown as a houseplant in our USDA Zone 5 area, the Desert Rose prefers a south- or west-facing window that allows for plenty of bright, indirect sunlight.
Because of its slow growth habit, expect to pay a little bit more than you would for an average houseplant. It is best to shop at a specialty nursery for these, but beware once you explore the world of caudiciforms, chances are you won`t be able to settle for just one.
Colorado State University Extension in the City and County of Broomfield provides unbiased, research-based information about 4-H youth development, family and consumer issues, gardening, horticulture and natural resources. As part of a nationwide system, Extension brings the research and resources of the university to the community. The Broomfield County Extension office is at 6650 W. 120th Ave., Suite A-3, Broomfield, 80020. For information, call 720-887-2286.
