Even the most novice gardener should be able to grow adenium plants. These "fat" plants (caudiciforms) are easy to grow because they are adaptable to a wide range of conditions, which makes them forgiving when they receive less-than-optimum care. Caudiciform plants form a fat, seemingly swollen stem, trunk, or aboveground roots and they are often given names such as Buddha belly or pregnant onion, along with many other colorful monikers.
If you are planning to grow one of these strange-looking plants, you can do so in almost any climate, but in most areas, you will be better off putting the plant in the highest level of light possible with the exception being locations that experience high temperatures, low humidity, and drying winds. Those conditions will require you to provide some shade.
When potting an adenium plant, use a bark-based, soilless potting mix that has been amended with coarse perlite to improve aeration and drainage. Three parts of the potting mix to one part perlite should usually be adequate. You can also use a potting mix created for cactus plants and other succulents.
To grow the plant from seed, prepare your container as above and then place the seed in the growing medium. You only need to barely cover the seed with the soil. Until seedlings appear, only water from below daily and from above once every three days.
If you have taken a cutting from the tip of a branch on an adenium plant, which is the proper place from which to take a cutting, allow it to dry out for a few days, then wet the end of the cutting and dip it in a rooting hormone. Stick the cutting into the growing medium recommended above. You can expect it to begin to form roots in two to six weeks.
Thoroughly water any time you water your plant, which means applying the water until the potting mix is saturated with the excess running out through the drainage holes. Doing so will reduce the chance of harmful excess soluble salt accumulation.
There are several things that have to be taken into consideration when determining the amount of time between waterings—growing conditions, whether or not your plants are in active growth, and size of your container.
As you become a more experienced gardener, you should be able to determine whether or not to water by lifting the pot up and checking the upper surface of the potting mix. Till then, you should allow the mix to almost become dry before you water again. Also, as your plants dry out, your adeniums will become much lighter when they are lifted, which is an indication that it may be time to water again.
Always be careful not to overwater your plants, although you should have a decent margin for error if you have used a mix with adequate drainage. On the other hand, if you underwater, it can be almost as destructive as overwatering, so don't allow your mix to become what I refer to as "dusty dry." This will exhaust your plant of moisture and destroy the delicate feeder roots.
Use a balanced blend, control-release fertilizer such as 13-13-13, which will give you excellent results by providing your adenium plants with the proper nutrition they need. You can buy these mixes in different release times that range from a couple of months to almost a year. Shorter release times are usually recommended by experienced gardeners as those fertilizers activate almost immediately. Applying a fertilizer with a shorter term will also allow you to time the discontinuation of feed more easily if you live in an area where your plants go through a period of dormancy in the winter.
The sap of Adenium boehmianum, Adenium multiflorum, and Adenium obesum contain toxic cardiac glycosides, which are poison and used to make poison arrows by hunters in Africa desiring to bring down some very large game. The poison is made from the fleshy parts of the trunk and the bark of the adenium plants, often in combination with poisons from other plants.
Poison is extracted from the adenium plants after they have flowered. The tuber is dug up and the sap extracted by heating the branches and roots over a fire until the sap discharges. Then, it is boiled in order to condense it to a thick syrup. The syrupy sap is then cooled and applied to an arrow point just behind the tip. Often, this sap is the sole ingredient for the poison arrow, although the latex of various euphorbia species (commonly called spurge) has often been added to the mix to make the poison especially potent.
Animals in the wild don't seem to be bothered by the poisonous compounds in the adenium plants, although some domesticated animals have died after eating parts of the plant.
© 2018 Mike and Dorothy McKenney