Adenium somalense var. crispum x obesum

Adenium somalense var. crispum x obesum

Family: Apocynaceae
Common Names: Adenium hybrid, desert rose
Accepted Name: Adenium obesum
Geographic Origin: This species is a hybrid between Adenium somalense var. crispum and Adenium obesum, and was created in cultivation by Mark Dimmitt. The parent species A. obesum originates from Eastern Africa, Northeastern Africa, and the Arabian Peninsula, while A. somalense var. crispum is native to the coast of southern Somalia.
Description: A. somalense var. crispum x obesum is an evergreen shrub or small tree that possesses woody, light brown stems and recurved, dark-green petals with a white pattern. The distinctive traits of each parent species are highlighted by the hybrid, including the petals and red flowers of A. somalense var. crispum, as well as the thin stems and above-ground caudex of A. obesum. Both parent species flower year-round, but are more floriferous during autumn.
Interesting Features:

The accepted name for Adenium somalense var. crispum x obesum is Adenium obesum, because the Adenium genus is considered to only include a single variable species. However, because of the considerable difference among varieties, botanists usually maintain the individual names, despite being unaccepted.
Under ideal conditions, Adenium species are capable of living for several hundred years.
In addition, all Adenium varieties are poisonous, and care should be taken when handling and siting.

Uses: All Adenium hybrids are very popular in cultivation for their beautiful flowers and unusual forms, and are maintained in a variety of gardens.
- Although no specific ethnobotanical uses are known for Adenium somalense var. crispum x obesum, the accepted species – A. obesum – has several ethnobotanical and medicinal applications which can be found on the species page.

Cultivation and Care:
- Watering: Moderate

Water moderately in the morning until water drains from the pot base.
Increase watering during the active growing season, and decrease irrigation in winter. However, never allow the species to completely dry out, as this will restrict growth and flowering potential.

- Soil Type: A very porous soil is required in order to prevent rot – use a cactus potting mix, or supplement regular substrate with pumice, sand, perlite, vulcanite, or brick chips.

Because this hybrid develops an above-ground caudex like Adenium obesum, it will not utilize the top 1/3rd of the soil.
When planting, ensure that the roots are buried beneath the caudex line. The pot should have several drainage holes on the side and bottom, but must not be very deep, as this will lead to the development of an underground oblong or carrot-shaped caudex.

- Lighting: Provide filtered bright light. Although the species is capable of surviving full sun outdoors, the caudex is very susceptible to scalding and protection is advised. However, under conditions with reduced light, leggy growth will occur, and flowering will be reduced.
- Propagation: Hybrids and cultivars must be propagated through cuttings or grafting in order to preserve the distinctive characteristics, while the parent plants are usually produced by seedstock. Grafting is the preferred method, as species propagated by cuttings have under-developed caudices.

In vitro propagation is a developing method for hybrids – however, further research is required to determine its viability.

- Cold tolerance: 30-50°F, USDA hardiness zones 10a-11b
- Special Accommodations: A. somalense var. crispum is more frost sensitive than other varieties, and A. somalense var. crispum x obesum should be offered the same protections. Cover or move indoors when temperatures drop beneath 50°F, and do not expose to humid or overly hot conditions.

Because the parent plant A. somalense var. crispum is very slow growing, hybrid plants may also require years to develop an impressive caudex. To encourage growth and support flowering, a fertilizer rich in phosphorous, potassium, and micronutrients should be applied regularly. However, do not use a fertilizer with a high nitrogen content.

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