Introduction to Adeniums :
Adeniums are arid land plants native to sub-Saharan Africa and although there are several species, Adenium obesum is the one that's frequently grown as an ornamental. It is an evergreen or drought-deciduous succulent shrub (which can also lose its leaves during cold spells, or according to the subspecies or cultivar). It can grow to 1–3 m (3.3–9.8 ft) in height, with pachycaul stems and a stout, swollen basal caudex. The leaves are spirally arranged, clustered toward the tips of the shoots, simple entire, leathery in texture, 5–15 cm (2.0–5.9 in) long and 1–8 cm (0.39–3.15 in) broad. The flowers are tubular, 2–5 cm (0.79–1.97 in) long, with the outer portion 4–6 cm (1.6–2.4 in) diameter with five petals, resembling those of other related genera such as Plumeria and Nerium. It comes up with multi-color flowers on the same pot, which makes it more beautiful.
Growing Conditions and Tips:
Because they can tolerate dry conditions, adeniums are well suited for the home environment being able to tolerate quite a bit of neglect. Keep temperatures high, preferably above 60˙F, although they can take it a bit cooler if grown very dry. Really the hotter, the better, so a 70˙F or higher air temperature is best.
In their native habitat, adeniums grow in full sun so they need good light to thrive. Direct sunlight is preferable, especially when they are in their active growth phase during the summer months.
Water Requirements :
Soil moisture is an important consideration in adenium culture. Their common name, Desert Rose, speaks to their ability to thrive with less water. Adeniums can tolerate higher moisture levels without harming the plant, as long as the temperatures are warm. As a general rule, be sure to let the soil dry out in between watering sand then thoroughly saturate the potting mix. Do not over-water adeniums when they are in their inactive growth phase during the winter months. If the soil is kept too moist, root disease can become a problem. During the slow growth time of year, it is best to water adeniums sparingly and err on the dry side. Once temperatures and day length have increased and new growth is visible, increase the amount of water. This will stimulate growth and flowering. Under very dry conditions, the plants can defoliate completely. Although somewhat unsightly, it does no harm and the plant will bounce back. A good rule to remember when growing adeniums is that high temperatures and full sun require more water and in cooler temperatures, the plants need less water.
Adeniums should be fertilised when they are actively growing during the spring and summer months. We recommend a balanced fertiliser with an elevated middle number (phosphorus) to assist in flower formation. There is a critical balance between too much and too little fertiliser since these plants are sensitive to elevated fertiliser salt levels in the soil. This can be seen on the plant with the symptomatic browning of the leaf edges. Generally, when watering succulents or other arid plants, the amount of water given should saturate the soil mix but there is often very little extra water moving through the soil. Therefore, when frequent doses of liquid fertiliser are applied, toxic levels can build up in the soil. For this reason, it's a good idea to periodically leach the soil with clear water by watering until you see water draining out of the bottom of the pot.
The only reason to prune your Desert Rose is for size management and to sculpt a nice shape. If you do prune, make sure this is done at the beginning of summer so the wounds heal and new growth will have time fill out the plant's form.
Spider mites are the greatest challenge as far as insects go. Since adeniums can tolerate dryness, and really need it, it's the perfect place for spider mite populations to grow and expand. Check your plants regularly for beginning infestations, especially when plants are brought in for the winter and they are subjected to warm, dry conditions. Mealy bugs can also affect plants but generally this is because there are other infected plants nearby.
Damage Identification and Control :
One of the most common problems is stem root and leaf disease. Stem rot occurs on the tips of the adenium desert rose plants and progresses down the stem. Leaf rot occurs in adeniums when the leaf is continually wet.
Leaf Disease :
Fist, leaf rot in adeniums is the easiest to treat. Just remove the effective leafs on the desert rose plant and move the location of the adenium so the leaves dry out. When you water try not to wet the leaves or if your plants are watered using sprinklers make sure you do it early in the day so the leaves have time to dry out quickly. Do not water adeniums in the evenings. If you are in the tropics or desert this is not usually a problem because even the nights are still warm enough to dry out the leaves of the adeniums fast.
Stem Roots Rot :
Desert rose plant stem root is caused by a fungus. It’s the most common problem with adeniums. The adenium rot is either black, dark drown or yellow. The actual desert rose rot part can be wet or dry and it processes down the stem of the adenium. When we see this we do not wait for the plant to fight the problem we cut the effective part off the plant. When cutting off the stem make sure you look inside the stem and make sure the adenium plant cut is far enough down so you only see good tissue with discolouration. Adeniums may stop this rot by forming an abscission zone. This zone happens more in desert regains than in tropical, humid and cooler climates. One sure sign of stem rot on desert rose plants adenium obesum is when the leaves start to fall off on the tip and turn brown.
White Leaf Fungus on Adeniums :
There is one leaf disease reported that we have not seen yet. It’s a white fungal adenium disease that affects the leaf first and then kills the rest of the plant. The fungus will spread to other adeniums quickly so if you encounter this problem remove the infective desert rose plant to an insulation area. If the problem gets to the stem then the plant usually dies. Since we have not encountered this problem we do not know if cutting off the infective stem will save the desert rose plant or not. Again the main cause of this and other leaf problem is caused by too much water. It’s important that the leaf of the desert rose plants does not stay continually wet.
Benefit of keeping Adenium as houseplant :
In general, Adenium is widely developed because it has attractive tree shapes and bonsai shapes. Adenium is a very beautiful plant.
Adenium has the benefit of being a native that is long-flowering, colourful, drought tolerant, low in its water demand and easy to look after. In fact, the main problem that most gardeners have when they first get one is overwatering. This can be avoided by growing the desert rose as a container plant and by keeping it in full sun. It thrives in both conditions. Desert rose is sometimes planted as a live fence and the wood is sometimes used as fuel
The medicinal benefits are, as a bonsai plant, treating wounds, treating the soles of the feet, taking care of skin beauty, relieving pain, treating toothache, treating ulcers.
You can check out a vast variety of grafted adeniums at : http://bit.ly/2wuVmza
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