The Arabian Desert is 90,000 square miles of drying winds, high temperatures, low rainfall -- less than four inches annually -- and saline soil. Few plants are adapted to the harsh environment, but the desert does have its flowers, and they are usually very bright ones. Some of them are adaptable enough to grow in other parts of the world. Others are odd desert creatures.
The oldest name for the desert rose is adenium arabicum. It grows throughout Africa and in the Arabian Desert and can be cultivated in humid tropical climates in other regions. The plant is a succulent shrub with a bulbous, swollen base and tubular flowers with flared lips. The flowers range in colour from white to pink to a deep reddish purple, and some plants are fragrant. Desert rose flowers bloom in small clusters throughout the year but will not bloom well unless they are in full sun. The plant will grow in a container that has excellent drainage; too much moisture makes desert rose vulnerable to pests and disease. It does not tolerate cold well and should be moved indoors in climates that experience temperatures below 4.44 degrees Celsius.
Desert hyacinth is a parasite. It doesn't synthesise chlorophyll itself and draws its nutrition from a host plant. Because the plant doesn't make chlorophyll, it isn't green. But the flowers are intensely yellow. They appear in a tight, dense cluster that is spike-shaped with buds featuring maroon tips at the top of the spike. Even without any green, the desert hyacinth manages to be colourful. It lives on salt-tolerant succulent host plants in the saline territories along the Arabian Gulf and survives partly because of an adaptation of its tiny seeds. The seeds will lie dormant for years until a host plant appears. Then the seeds germinate and the desert hyacinth blooms on a new host.
Acacia tortilis is commonly known as the "umbrella thorn" due to its wide crown and long, sharp thorns. The tree is found everywhere in the dry environments of Africa and the Middle East, including the Arabian Desert. It is a significant browse plant for desert animals and a favourite of camels. The plant produces pale yellow or white flowers in small, round clusters. There may be as many as 400 fragrant flowers per twig on the tree. Ninety per cent of the flowers fall from the tree and are eaten as forage, often by goats. The pods and leaves of the acacia contain digestible protein and are sold as food for animals and people. The acacia is extremely drought-tolerant and is usually the tree that grows farthest into the desert. One reason it can survive months of drought is its deep taproot and wide root web -- the tree digs down into sandy soil or spreads a web of subsurface roots bigger than its crown in shallow soil.