What you need to know about desert rose Name: desert rose (Adenium obesum). Height: up to 2m in the ground, but more often pot-grown; ideal for bonsai. Foliage: elongated, mid green, tough; deciduous. Climate: sub-tropical to tropical, arid; warm temperate frost-free climates; tolerates cold nights. Soil: prefers well-drained, gritty soil, but tolerates richer loams. Position: sunny open spot; light shade from hot midday/afternoon sun will reduce leaf scorch. Flowering: single rose-like flowers in variety of colors and combinations, predominantly pink, white and red. Feeding: use a long-term controlled-release fertilizer sparingly. Watering: water when conditions are hot and dry; good drainage is essential. Don't water over dormant period. Appearance and characteristics of desert rose Desert rose is a succulent, but unlike most succulents, it doesn't have swollen leaves. Instead, it has a swollen, belly-like trunk known as a caudex, which acts as a moisture store. It more closely resembles a bottle tree or baobab than a typical succulent. As the plant ages, the caudex expands and may divide to form a buttress (see the bonsai example above). Its branches and stems look like those of a frangipani. Its leaves are smaller and mid-green. Desert rose flowers are very like those of oleander, allamanda and frangipani in shape. They have five equally sized and spaced petals surrounding a central yellow "eye" with each on its own short stem. Color ranges from pink through to deep red, with many variations and combinations available. Flower size will depend on growing conditions, but is on average around 5cm across. How to plant and grow desert rose Growing desert rose from seeds Growing desert rose from seeds can be tricky. The plant does set seed after flowering, but the resultant seedlings are variable. For a true-to-type plant, take stem cuttings when dormant or buy a named variety. How to plant a desert rose Desert rose can be planted outside in the garden in warm to tropical and arid climates, but it is most commonly grown as a potted plant or bonsai. It is not an "indoor" plant – it can be taken inside for short periods while in flower, but prefers being outside in a warm, sunny spot, out of chilly winds. If planting desert rose in the garden, follow these steps: Choose a sunny position; in tropical and arid areas some light shade from midday will protect it from scorching. Plant so the base of caudex (trunk) is at or just above soil level – never "bury" a desert rose. Soil should be free-draining and gravelly, but a richer loam will be tolerated. Add a long-term controlled-release fertilizer during soil preparation. If planting desert rose in a pot, follow these steps: A porous terracotta or clay pot is preferred, as it drains well and dries out more quickly than plastics, ceramics or fiberglass. Add a shallow layer of pebbles or "crocks" in the base of the pot to further improve drainage. Use a premium-quality cactus and succulent potting mix. Set your desert rose in the pot so the base of its caudex is at or just slightly above the top of the potting mix. Position the pot in a sheltered spot for a week or so to overcome transplant shock, then move into the light. Light shade from midday will minimize leaf scorch. If planting desert rose as a bonsai, follow these steps: Choose a shallow bonsai pot or bowl that is in proportion to the size of the plant. Ensure the pot has plenty of drainage holes. Remove the plant from its pot. Trim the roots so the base of the caudex will be above the rim of the pot or bowl and the roots will fit neatly inside the pot. Trim a piece of flywire mesh to neatly fit inside the base. Holding the plant in position, fill in and around its roots with a premium-quality bonsai potting mix. Water well to settle the mix. Trim the top growth to start the training and shaping process. Place the pot in a sheltered spot for a few weeks before gradually introducing it to an open position. Provide light shade from midday onwards if possible. Caring for desert rose Like other succulents, desert rose does need regular watering, especially in hot, dry weather. Promote flowering with a water-soluble or liquid fertilizer in spring and summer, diluted to about one third of the recommended strength on the label. A long-term controlled-release fertilizer can be added around plants in the garden and pots once a year. Again, use it sparingly. Pruning desert rose When grown in the garden, desert rose responds well to light pruning to keep it shapely, in much the same way that a frangipani is pruned. Cut back only in the dry season to avoid infections entering cuts. A bonsai desert rose should have its tips nipped out every few months, but do take note of where flowers appear from and don't trim back past these points before flowers have appeared. Diseases and pests affecting desert rose Desert rose is reasonably free of diseases, and rarely troubled by pests. If aphids or mealy bugs are present, a light spray with white oil or insecticidal soap may be applied.
