Black desert rose is a variety of Adenium obesum [ah-DEEN-ee-um oh-BEE-sum] grown for its stunning, black flowers.
In its native habitat, the Adenium plant grows in the tropical and subtropical regions of Africa and Arabia. In proper botanical terms, Adenium obesum is not a rose but a succulent, like cacti. More Desert Rose plant varieties.
It has a few common names, including:
- Black adenium
- Black fire desert rose
The black Adenium obesum [ah-DEEN-ee-um oh-BEE-sum] thrives as a perennial in hardiness zones with a year-round tropical climate. It grows as an annual in colder climates.
The plant is evergreen, though Adenium drops leaves during times of extreme drought stress.
The handsome, striking flowers make a unique addition to flower displays. Like most other black flowers, the pigments are not truly black but a very dark blue or deep red.
Black color does not occur naturally but arises from careful breeding to increase the anthocyanins – a dark pigment – present in the petals.
Growing The Purple Black Desert Rose Plant
Black adenium, like other succulents, thrives on an easy caretaking regime. The plant survives in poor, dry soils and consistent temperatures of the desert.
That means black Adenium survives with minimal care.
Producing flowers takes a lot of energy. This means coaxing the rich, dark blossoms requires some extra attention to detail.
Size and Growth
Desert rose has a caudiciform shape. This means it has a broad, bulbous base or stem that seems unusual for its size. The plant can grow two to five feet tall and one to three feet wide.
The base consists of a woody stem that separates into a beautiful weave at the root ball.
The leaves grow sparsely. Fewer leaves help cut energy expenditure and exposure in the harsh desert sun.
The leaves have a leathery texture and dark green color.
Black Adenium Flower and Fragrance
The flowers themselves range from 1 1/2″ – 2 1/2″ inches wide and 1/2″ to 2″ inches deep.
The tubular flowers come with five petals. Color variation may occur in color within flowers on the same plant.
The black desert rose Adenium has a minimal scent. They may produce a lightly spicy, cinnamon-flavored fragrance.
Light and Temperature
Black adenium needs conditions that approximate its desert origins. This means full, direct sunlight. The lighting requirements increase during the summertime when grown in temperate regions.
This time of year will bring the most active growth, whether grown indoors or outside.
Adenium does well with warm temperatures, between 70° and 100° degrees Fahrenheit. When grown in colder climates, the plant needs to move indoors for more stable temperatures during the winter.
The vigor starts to decline below 60° degrees Fahrenheit, and the plant may even die.
Watering and Feeding
Like other succulents, the Adeniums do well with a little “neglect.”
It handles dry conditions well. Even with extreme drought, it may drop some leaves. Getting the right moisture levels plays a crucial role in getting the most out of the plant.
During the summer, the soil should get a full soak but dry out between waterings.
Drying out time depends on the pot’s size and the potting mix used.
It may take anywhere from a few days to a week to dry out. During the winter, the plant needs less watering.
Fertilizing helps the Adenium during the spring and summer growing season. To encourage blooming, use a fertilizer with a high phosphorus content (middle number).
Soil and Transplanting
Use well-drained soil like a good cactus mix. Add extra perlite and sand to help the drainage and keep the moisture levels needed for the best growth.
Transplant in early spring when plants are beginning to become active. To prepare the plant to thrive in its new setting.
- Shake off the old soil
- Prune branches if needed
- Remove any unhealthy-looking roots
Grooming and Maintenance
Once established, the black Adenium has minimal care requirements. It will tolerate pruning and even grow as a bonsai.
Adenium has toxicity that indigenous cultures have used for years to poison arrow tips and shock fish ponds. It’s crucial to keep the plant away from any pets who may sneak a nibble.
How To Propagate Black Adenium Obesum?
Desert rose does propagate from cuttings.
- Take a small tip cutting and let it dry out for a day or two.
- Dip the cutting in a rooting hormone powder
- Place the cutting into a well-draining potting medium
- Place cutting and rooting container in bright indirect lighting
- Keep soil moist, not wet
- Once roots begin to form repot into a new container
Black Desert Rose Pests or Diseases
Like most Desert Rose, the Black adenium has few health issues.
Overwatering causes the biggest problem.
Overwatering leads to stem, root, or leaf rot. Stop watering and let the affected portions dry out.
Insect pests focus on new growth. Keep an eye out for plant scale, mealybugs, and Adenium aphids. Control with Neem Oil sprays.
More on Desert Rose Pests here.