Adenium Root Rot

Adenium Root Rot

Adenium plants belong to the family Apocynaceae, and are slow-growing with thick, succulent stems and deep pink flowers. These ornamentals are native to Africa, Madagascar, the Middle East and the Arabian Peninsula. They are also called desert rose, sabi star, mock azalea and impala lily, and, like most plants, are prone to root rot if grown in poor conditions. Read on to learn about how to identify and remedy this disease.

Signs of adenium root rot 

If you notice the appearance of pimple-like spots, it is a sign that there is too much water inside the stem and the root, or the caudex and axis. The spots are the plant’s way of creating exits to eliminate excess water, and indicate that the roots below are in trouble and rotting. You will also notice that the caudex is swelling up to an unusual size. 

Another indication of root rot is yellowing leaves. If you press the leaves a couple of times and they do not fall off, the plant is likely suffering from a root disease like root rot. When you prune back the branches, the new leaves will develop slowly and will be very small, and there will be few, if any, blooms. This means the plant’s growth is stunted and is another indication that the plant may be suffering from root rot. 

Causes of adenium root rot 

The most common cause of root rot among adeniums – and all plants –  is poorly-draining or overwatered soil. The soggy condition of the soil prevents the roots from absorbing the oxygen they need to survive, and the rot will spread to healthier roots once the oxygen-starved roots die and decay.

Soil fungus is another cause of root rot, and weakened roots are more susceptible to this. Certain species of fungi, such as Pythium, Rhizoctonia and Fusarium, thrive in moist soil conditions and cause root rot. Armillaria, a notorious fungus also known as shoestring rot, is also a culprit of root rot in certain plants. 

Ways of dealing with adenium root rot 

Remove the rotten plant parts.

Cut or trim back the rotten plant parts using a sharp knife, scissors of shears. Cut away a large part of the caudex if necessary, to ensure you remove the entire affected area. Sterilise your tools between cuts to avoid spreading the infection. When you are done cutting, apply garden lime powder or cinnamon to the fresh cuts to help protect them from bacteria and facilitate wound healing.

You can also use a high-pressure garden hose to blast off any rotten parts of the roots. This allows you to save more of the unaffected parts and you will not need to sterilize your tools. 

Another option, if you want a gentler approach, is to remove the rotted part of the caudex with a spoon. This is a simple and effective method, but takes a little more time than the other methods. 

You can soak the plants in a fungicide solution after checking the roots. The solution will kill harmful bacteria. You may also opt for gentler solutions, like lime or a ginger-garlic-chili solution. 

Allow the plants to dry out in the sun. 

Lay the plants’ bare roots under the sun so they can heal after you have cut off the rotten parts. Once the roots have dried out and become harder, you can plant them in the soil again. 

Replant the adeniums in the new soil.

After the plants have healed, you can plant them back in the soil. Rooting hormones are often used to promote the formation of new roots. Do not water the plants too soon after replanting them; once you see little strings coming emerging from the roots, you may start watering the plants lightly. As the plants grow stronger, you can increase the water and add fertilizer as well. 

Conclusion 

Adenium plants are slow-growing ornamentals that are native to Africa, Madagascar and the Middle East. Like most plants, they are susceptible to root rot, and the most common causes are overwatering and soil fungus such as Fusarium. To handle adenium root rot, trim off the rotten plant parts and soak the plants in a fungicide solution. Allow the plants to dry out in the sun and replant them using fresh potting soil. 

Image: istockphoto.com / mansum008