Adeniums, a genus of the family Apocynaceae, are visually stunning dwarf shrubs and small trees with swollen roots and trunks that form interesting shapes and blooms of vibrant red, white, pink and variegated hues. Adeniums, often mistaken for desert plants, originated in the tropical regions of Africa and Arabia. Whether grown as an ornamental container specimen or in the landscape of warmer climates, adeniums are a magnificent and interesting addition.
Adeniums thrive in locations where temperatures are moderately hot, up to 95 degrees F. Southeastern states where humidity is higher provide additional benefit to these semi-tropical specimens. For those who live in colder Northern locations, adeniums can be grown in containers and moved indoors in places where temperatures fall below 50 degrees F.
Though adeniums grow well in desert climates, they need to be treated as the tropical plants that they are. Daily watering during the high heat of summer and consistent moisture during active growth creates the best environment for growth. For adeniums grown in warm climates where temperatures remain above 50 degrees F at night, continue to water regularly throughout the winter, allowing soil to dry out between each watering.
Adeniums need sunlight for proper development. In cloudly locations, the plants tend to become spindly and develop less vibrant blooms. Full sun is preferred; however, desert-grown adeniums can withstand 30 to 50 percent shade in desert locations. Do not rotate potted adeniums in hot climates, as the sun can burn and destroy foliage on previously shaded sides.
Adeniums need regular feedings to develop their swollen trunk and root structure. Use a balanced 20-20-20 fertilizer according to manufacturer's directions for best results. Apply only when soil is moist. Do not allow fertilizer to touch foliage or trunk, as this can cause burns.
Adeniums require special care when they enter dormant periods in cooler climates. When water absorption slows and foliage begins to yellow and drop, reduce watering dramatically and stop when temperatures fall below 50 degrees F. Move containers to a dry, frost-free location and water very sparingly (once a month) throughout the winter. When terminal buds appear and expand in the spring, gradually increase water amount and frequency as the plant enters another growth cycle.
Adeniums need ample space to achieve maximum root growth. Choose thick-walled bowl-shaped pots to avoid destruction caused by expanding roots. As long as the potting medium is well-draining, there are many varieties that can be used. Experiment with different combinations to find the best mix for your particular plant. Repotting should take place early in the active growth period. In order to create the interesting root formations, elevate the adenium slightly with each repotting. As the lower roots expand, the upper portion will twist and contort.