Adenium obesum....all you need to know!

Care and how to grow

There are five varieties of true Desert Rose, and all are native to arid or semi-arid climates, yet they can all adapt well to tropical and semi-tropical settings.

Indeed, these rugged desert dwellers adapt to almost any situation as long as they have plenty of sun and warmth and well-draining soil.

In very hot climates, Desert Rose is happy and prolific outdoors all year round. These plants love to be in the direct sun with temperatures of at least 70°F, but they can do very well in temperatures of up to 100° Fahrenheit.

In North America and other settings where the temperature drops below 40 degrees Fahrenheit for extended periods of time, the plant is abundantly floriferous throughout the warmer months.

The blooms are long-lasting and are attractive to hummingbirds and pollinators such as bees and butterflies. When the weather begins to cool, you must bring your Adenium indoors to enjoy during the winter.

Adenium is a sun-lover

The desert rose flowering plant grows well in desert settings and will bloom beautifully with full, bright sun. They can also do well with bright morning sun or bright afternoon sun but may not flower as heavy. If kept in the shade, these plants become leggy and weak-stemmed.

Even though bright sun stimulates blossom production, the Desert Rose takes a break during the very hottest and rainiest months of the growing season. This results in two periods of blooming. You’ll see flowers begin to develop in early spring. With the right amount of light, your plant should bloom steadily until mid-summer.

At this point, blossoming will cease for 6-8 weeks only to resume in the early autumn months. When the weather begins to turn cold (55 degrees Fahrenheit or less on a consistent basis) give your plant a good pruning and bring it in the house.

In a very bright, warm environment such as a greenhouse, Adenium can remain active throughout the winter months. If you bring your plant into your house for the winter, it will probably stay in a semi-dormant state until spring arrives. During this time, just keep it in a warm room with bright, indirect light.

Water moderately in warm weather and sparingly in cool weather

The Desert Rose enjoys a nice, warm rainy season, but when cool weather comes, you’ll need to cut back on watering. Some say it is best to think of your Adenium as a tropical plant in the spring and summer and as a cactus in the autumn and winter.

The most important thing to keep in mind is that the roots must never become waterlogged. During the growing season check the soil every few days in container plants. When the plant is completely dry, water slowly and carefully. Saturate the soil, but do not soak it. The soil should be moist, not wet, and there should be no standing water. Use a well-drained soil and allow the soil mix to dry out thoroughly before watering again.

If you plant directly into the landscape, be certain to position your Adenium on a bit of an incline so the water can drain off after heavy rains. The Desert Rose growing outdoors are amazingly drought tolerant and may not need watering once established. In times of extreme drought water deeply, occasionally with a slow drip for several hours during the coolest part of the day.

Desert Rose fertilizer

During the growing season, it is a good idea to provide a light feeding of a slow-release fertilizer, or a water-soluble liquid fertilizer from time-to-time. In the springtime when the plant is rousing from its winter rest, you can give a diluted feeding once every couple of weeks. During summer, reduce this to once a month. As the weather cools, stop feeding so that the plant can wind down for the winter.

If you bring your Adenium plant indoors for the winter, you may want to give it one weak feeding in mid-winter; however, this is not necessary as the plant is likely in a state of semi-dormancy.

Is regular pruning necessary?

Because these plants can grow quite large, a combination of pruning and under-potting is essential to keep them at a manageable size. A regular pruning schedule will help keep your plant fresh, vigorous and well-groomed.

During the growing season, pinch back or prune unruly growth. Before bringing the plant indoors for winter, prune back excessive growth as this will make the rest period more effective for the plant. Additionally, it will be easier to keep a smaller, more compact plant indoors during the winter months.

Before putting the plant back outdoors for the growing season, a good trimming is a smart idea. Trim off any dead or damaged vegetation. Cut back straggly branches to improve the plant’s shape. You can use these branches as cuttings to create new plants.

What kind of container is best for Desert Rose?

Many lovers of Adenium grow their plants or look to repotting desert rose into terra cotta clay pots instead of plastic to keep them on the dry side.

You can use containers made of almost any material when planting Desert Rose. Just be sure the container is sturdy because Adenium‘s aggressive root growth can burst flimsy plastic containers. Any growing container must have drainage holes in the bottom. If you use a saucer, you must not allow water to stand in the saucer.

For better air circulation to the roots, a porous container material is better than a nonporous material. For this reason, many experts recommend using terra-cotta containers instead of plastic ones, plus the shallow terra-cotta bowl makes a nice presentation. Well-made wooden planters might also be a good idea.

Another interesting option might be unique, homemade containers fashioned from hypertufa, a lightweight, durable, porous material you can mix up yourself using concrete, sand and peat moss or coco coir. Regarding planter shape, low, wide planters and containers are preferable to tall, thin ones. A lower, wider container will encourage the roots to spread and provide a more stable base for the plant.

If you plant an adenium in a tall, thin container, the root structure will be more carrot shaped and not provide much stability. This can be a plus if you hope to create a thick, attractive caudex.

It is possible to start an Adenium cutting in a tall, thin container and then transplant it later into a short, squat container leaving quite a bit of the interesting root exposed.

How often should you repot Desert Roses?

These plants are relatively slow growing, and they should not need repotting more often than once every two or three years. Be careful not to provide an oversized container as this will encourage root growth and may detract from the number of blooms your plant produces.

Select an attractive container that gives your plant’s root mass one or two extra inches for growth all the way around. Be sure to shake the old soil off the roots and replace the soil entirely with fresh, new, nourishing soil mix.

Like other succulent plants, plant the desert rose succulent using a cactus potting soil. These plants want a well-draining soil to prevent stem and root rot.

Propagation of Adenium plants from cuttings and seeds

When you start Desert Rose from a cutting, the resulting plant will not develop a thick, interesting root structure above ground. The caudex will develop below soil level and can later be exposed without harming the plant.

The advantage of starting from a cutting is that you can do lots of interesting things such as grafting cuttings that produce one flower color onto plants that produce another color. You can also graft several different cuttings together to form an artistic grouping.

In Europe, you sometimes find the Desert Rose grafted onto an Oleander stock. The Oleander graft combination allows the Desert Rose to grow faster and produce more flowers.

The basics of starting Adenium obesum from cuttings:

If you have a plant sending out long shoots, it’s a good idea to prune as a way of guiding and controlling plant growth. You can use the pruned sections to create brand-new, interesting plants.

Cuttings at least 6″ inches long make the ideal succulent stems for rooting. After pruning the plant, sort through the shoots and select the best ones. Lay them out on newspaper or a paper towel in a warm, dry place out of direct sunlight. Allow the cuttings to dry for 48 hours.

After two days, prepare a pot or container with a gravelly, well-drained potting mix. You can use a commercial mix intended for use with cactus and succulents or make one using equal amounts of potting soil, coco coir or peat moss, sand and/or very fine gravel. Remember to put a layer of coarse gravel in the bottom of the container for good drainage.

Dust the cut end with rooting powder and poke it into the planting mix. Use a spray bottle to thoroughly soak the planting mixture. Mist every couple of days to keep the soil moist but be sure not to allow it to become thoroughly drenched. Desert Rose does not like to be waterlogged, and the roots will quickly rot if you allow the soil to stay too wet.

Place your developing plant in a warm, bright; still, area either indoors or outdoors and keep a close eye on it. If you are using an indoor location, be sure to turn the growing plant every day or two so it will get even sunlight. Otherwise, it will tend to bend toward the sun.

When it begins to sprout new leaves, you’ll know it is well-established enough to move the young plant to a sunnier place. Mature, well-established Desert Rose plants enjoy bright, full sunlight. They can be planted directly into the ground outdoors, but because they are tropical and not cold hardy at all it is usually better to plant them in containers so make moving indoors for the winter easier.

How to harvest Desert Rose seed pods

The advantage of propagating Desert Rose from seed is that you can be sure of growing plants that develop the thick, bulbous, fat base above-ground caudex that makes these plants so interesting and attractive. It will take several years for the Caudex to develop so be patient!

You can buy Adenium obesum seeds online or from specialty nurseries; however, be careful to get fresh seed. The fresher the seed, the better your results will be. If you have several plants for cross-pollination, you can harvest desert rose plant seeds from your plants at the end of the growing season and plant the seeds in the springtime.

For seeds on your plants, look for the development of bean-like seed pods. These usually appear in pairs. As the pods ripen, they will begin to look swollen. At this point, you may want to place a net bag over the pods and secure it with a twist tie, twine or a rubber band. This will prevent your seeds from flying away when the seed pod bursts.

When the pod bursts, gather the seeds and remove the dandelion-like fluff from the ends. Plant the fresh seeds right away for best results.

How to sow Desert Rose seeds

To plant seeds, start with a growing medium of 50% peat moss or coco coir and 50% sand or perlite – I like perlite. Use a shallow pot or a tray placed in an area with bright indirect light. You may want to use a warming pad to keep the growing medium at a steady temperature of 80 to 85°F.

Evenly sprinkle the seeds over the surface of the growing medium and cover them very lightly with a thin layer of sand. Use a spray bottle to saturate the growing medium evenly with water. Repeat this process on alternate days until the seeds sprout.

Expect to see sprouts within a three to seven days. Continue misting them every couple of days to keep them lightly and evenly watered. Seedlings should be large enough to transplant into individual containers in about a month.

Turn your Adenium on its head!

If your plant has become unmanageable or fallen into disarray, you might want to start all over with seeds or cuttings or turn your old plant upside-down. This creates a very novel presentation and could be extremely interesting in an artistic container.

To create an upside-down Adenium, prune the twigs and branches back fairly close, but do a few short stems for new growth.

Prepare a container just as you would when starting cuttings or repotting a Desert Rose.

Remove your plant from its original container and wash the root ball. Trim back long, straggly roots for a better appearance and then pot the whole thing upside down with roots sticking up and the top of the plant underground.

Take care of it just as you would a right-side-up Adenium.

Within a couple of weeks, you’ll see sprouts emerging from the sides of the root mass. Before you know it, you’ll have leaves, blossoms and an interesting looking dark root mass with tendrils adapted for photosynthesis by turning slightly green.

Desert Rose pests and problems

The most pervasive problem for Desert Rose is root rot. The importance of avoiding over watering cannot be overstated. These plants retain water in their thick roots. They do not need or want to stand in water, so it is far better to err on the side of underwatering when it comes to watering. Remember to water sparingly and make sure your plant’s drainage system is working properly.

Pests that may bother Desert Rose plants include:

• Aphids
• Spider mites (tetranychus urticae)
• Mealy bugs
• Several types of plant insect scales. If you find your plant has a problem with one of these pests, treatment with neem oil insecticides should provide a proper remedy.
• Oleander caterpillars may also cause problems for Adenium. If you notice caterpillars on your plant, pick them off by hand (wear gloves) and treat the plant with Bacillus thuringiensis (Bt) as quickly as possible. These caterpillars can defoliate your plant very rapidly, but if this happens don’t despair. Once the caterpillars are under control, the plant will spring back with new dark green leaves very quickly.
• A fungal disease called Anthracnose is sometimes a problem for Adenium. If your plant’s leaves develop tan lesions and then turn yellow and fall off, Anthracnose is probably the problem. Again, don’t despair. This disease usually occurs in the early summer and/or in the autumn and resolves on its own. Just reduce watering and rake up the fallen leaves to remove the fungus spores. Your plant should recover nicely.

A single specimen of one of these rugged, long-lived plants can provide a wealth of gardening enjoyment. They can be planted in the landscape, maintained as container plants, kept as bonsai, grafted together, grafted with oleander or even planted upside down to create visually fascinating shapes and displays.

Long-lived Desert Rose is the sort of plant that becomes a member of the family. In the wild and in ideal settings, these plants can survive and thrive for centuries.

In areas with cooler climates, the care needed by these interesting plants provides a touchstone for the transition from season-to-season.

The plant celebrates the spring, lounges in the heat of the summer, revives in the autumn and hibernates in the winter. As you care for and enjoy this interesting botanical specimen through the seasons and years, you will surely grow to think of it as a good friend.