The desert rose (Adenium obesum) is a slow-growing plant, only growing about 12 inches per year. It is often used as a bonsai plant thanks to its thick succulent trunk, thin and delicate leaves, and luscious, deep pink trumpeting flowers. It is native to Africa, the Middle East, and Madagascar. The desert rose is the only Adenium extensively hybridized to obtain different flower colors (like orange and striped). In many tropical and warmer climates (USDA zones 11 and 12), it's a widely used ornamental outdoor plant, and in cooler zones, it's kept as an indoor plant. It's best planted in the spring. It will die if kept outside in freezing temperatures. A member of the dogbane family, the sap of the desert rose plant is toxic to people and pets.
|Common name||Desert rose, Sabi star, mock azalea, impala lily|
|Botanical name||Adenium obesum|
|Mature size||3–9 ft. tall, 3–5 ft. wide|
|Soil type||Sandy, well-drained|
|Soil pH||Neutral to acidic|
|Flower color||Pink, red|
|Hardiness zones||11, 12 (USDA)|
|Toxicity||Toxic to humans, toxic to pets|
Desert Rose Care
Tending to a desert rose plant is simple, but it does take some finesse. Similar to other succulent plants, it needs careful water management and lots of sunlight.
The plant also prefers consistently warm temperatures, which is why it is an indoor plant in many parts of the United States (except for USDA zones 11 and 12). The plant typically blooms during the summer months, erupting with vibrant pink and red flowers and bright green leaves. When it goes dormant for the winter season, it drops its flowers and foliage.
The desert rose plant thrives in a full sun environment, so choose a spot in your home to house the plant that gets ample light throughout the day, like a bright windowsill or sunroom. If you live in an area where the desert rose plant can be grown successfully outdoors, select a spot in your garden that is not shaded by taller plants but has some protection from high-noon sun, which can scorch the plant's leaves.
As its name implies, the desert rose plant is used to naturally dry, desert-like conditions, including well-draining, sandy or gravelly soil. The soil should have a neutral to acidic pH, ideally hovering right around 6.0.
The desert rose plant has varying water needs, depending on the time of year and temperature. During its growing season (late spring and summer), the soil of the desert rose should be kept moist but never saturated. Check on the soil periodically. Allow it to dry out completely before administering another watering. Additionally, plant your desert rose in a vessel that has ample drainage holes. It can be susceptible to rot if it becomes too moist (a clay or terra cotta pot can also help with excess moisture).
Come the fall and winter months (when the plant typically goes dormant in the wild); you can reduce moisture drastically, watering only minimally once a month or so. If you're curious if your plant is getting enough water during its growing season, you can look to its trunk for the answer. A swollen, thick trunk (in proportion to the size of your plant) is a great indication that your plant is well-hydrated.
Temperature and Humidity
You should keep your plant in warm temperatures at all times—it will die quickly if exposed to prolonged temperatures cooler than 50 degrees Fahrenheit. It thrives best at temperatures between 65 and 90 degrees. If you've planted your desert rose outdoors, it will not likely survive any prolonged frost. Humidity is not important to the desert rose. It's used to a dry, hot climate.
For an added dose of nutrients (and potentially more flowers), you can feed your desert rose with liquid fertilizer (diluted by half) once a month during its active growth period. Do not fertilize the plant during its dormant period.
Types of Desert Rose
There are many species of Adenium. However, the most common and easiest to find is Adenium obesum. Some other subspecies include:
- Adenium obesum subsp. oleifolium: Native to South Africa and Botswana with a large tuberous stem, narrow blade-like leaves, and tubular flowers
- Adenium obesum subsp. socotranum: Native to Socotra, an Indian Ocean island between Somalia and Yemen; this is the largest of the species, rising to 15 feet tall
- Adenium obesum subsp. somalense: Native to Eastern Africa; has narrow blade-like leaves and twisting branches
- Adenium obesum subsp. swazicum: Dwarf species, usually doesn't get larger than 2 feet tall; native to Swaziland and South Africa
Sterilize your pruners between plants using rubbing alcohol or a bleach solution. Remove cold-damaged growth as soon as new growth emerges. Trim long, lanky stems to equal out the stem growth symmetrically. Remove branches that rub or cross other branches, cutting just above a leaf node or where the stem joins with another stem.
Propagating a Desert Rose
Desert rose can be grown from branch cuttings and seeds. If you grow the plant from a branch cutting, you may fail to get a characteristic bulbous trunk like you would if you propagate from seed. To propagate from a stem cutting, here's how:
- Before you get started, get gloves, sterilized pruners, rooting hormone, a clean pot, and a well-draining potting mix.
- Since the sap of this plant is toxic, use gloves when cutting this plant. Using your pruning snips, take a 5- to 6-inch cutting from the tip of a branch.
- Allow the cutting to dry out for a day or two. Wet the cut end and dip it in rooting hormone.
- Plant the cut end into a well-draining growing medium like perlite or sand mixed with soil. Water the cutting daily; however, make sure the water drains out of the soil. The cutting should take root in about two to six weeks.
- After six weeks, you should notice new growth, or if you try to tug at the stem gently, it should feel rooted in place.
How to Grow Desert Rose From Seed
The best time to sow desert rose seeds is in the spring. Get a well-draining potting mix with perlite or use a sand and soil mix. You can soak the seeds in advance for several hours or a day to rehydrate them, then place one seed every two inches in your growing medium. Cover lightly with a thin layer of soil mix.
Water thoroughly and keep the plants in a warm location. Only water the soil once it begins to dry out. You can also mist the soil or water from below, but do not allow it to get waterlogged. Once seedlings sprout, usually in 7 to 10 days, move to a sunny spot.
Potting and Repotting a Desert Rose
Repot the desert rose as needed, usually when the roots overtake the container. This can be once a year or every other year. If you do not want your plant to grow much larger, you can keep it in its current container. Keeping a plant rootbound slows down its growth. The best time for repotting is in the late winter or early spring, preferably as soon as new growth emerges.
When repotting a succulent, make sure the soil is completely dry before gently removing the plant from the pot. Knock away the old soil from the roots and remove any rotted or dead roots in the process. If you make any cuts or notice bruises, you can topically add a fungicide or antibacterial solution.
Place the plant in its new pot and backfill with potting mix, spreading the roots out as you repot. Leave the plant dry for a week or so to reduce the shock to the plant. After a week, water the plant but make sure it drains thoroughly. Do not leave the plant in standing water or soggy soil.
Desert rose cannot endure frost or prolonged cold. Once temperatures reach 50 F, the plant will drop its leaves and trigger dormancy. To keep your plant alive, remove the plant from the outdoors. You can bring the plant inside, stop watering it, and place it somewhere it will not freeze, like a garage or basement that remains above freezing. It will not need care or light until the spring. Once the warmer temperatures return, slowly give water, place in a window with sun exposure, and gradually reintroduce your plant to outdoor life.
How to Get Desert Rose to Bloom
Adenium flowers about seven to eight months after sowing, depending on the cultivation conditions. To encourage blooming, make sure your plant gets at least six hours of sunlight and provide fertilizer at least once a month during spring and summer. If your plant was recently repotted, it may be putting its energy into developing new roots instead of flowers. Give it time to adjust to its new growing environment.
Common Problems With Desert Rose
Desert rose is a relatively disease- and pest-free plant. The biggest problem affecting this plant is overwatering. When growing conditions are out of whack for a plant, it reduces its natural defenses, and pests or diseases creep in.
Yellowing Leaves or Leaf Drop
A common sign of root rot is yellowing leaves or sudden leaf loss. A fungus causes root rot. If caught early enough, you may be able to save the plant. You will need to remove damaged leaves and stems and unpot the root ball. If you notice any blackened, mushy root, cut away the damaged root with a sharp knife. Between cuts, sterilize the knife. Apply a fungicide, according to the instructions. Replant the remaining root in a well-draining potting mix.
Spotting on Leaves
Powdery mildew leaves blister-like marks on the upper leaf surfaces. It can lead to distorted growth and a white powdery-looking substance on the leaves, stems, and buds. This tends to spread more often during cool, damp nights and warm days. Powdery mildew does not like water. Mist the plant leaves and apply a fungicide, according to the instructions on the package. Prune when stems and branches bunch up; having adequate spacing between plants reduces the risk of powdery mildew.
Speckling of Lower Leaves
Spider mites are the most common pest to go after desert rose plants. They feed by sucking sap, primarily from the underside of the leaves. Leaf speckling leads to complete discoloration and eventually leaf death. To detect spider mites, shake the infected foliage over a piece of white paper; spider mites appear as small dots. You will also notice fine webbing and eggs on the underside of the leaves. To get rid of a small infestation, use a forceful spray of water on the underside of all the leaves. Repeat this every several days. You can also use insecticidal soap or neem oil for mite control. Make sure you apply it to the underside of the leaves and all the lower surfaces of the plant.
Is desert rose easy to care for?
Desert rose is an easy plant to keep and resistant to drought and most pests and diseases.
How fast does desert rose grow?
Desert rose is a slow-growing plant not growing more than a foot a year.
How long can desert rose live?
This plant is a long-lived plant; in the right conditions, it can span centuries.
Hossain, Md Amzad. “A Review on Adenium Obesum: A Potential Endemic Medicinal Plant in Oman.” Beni-Suef University Journal of Basic and Applied Sciences 7.4 (2018): 559–563. Print.
American Society for the Prevention of Cruelty to Animals. “Desert rose." Aspca.org. N.p., n.d. Web.