Alocasia plants can be vulnerable to fungal diseases such as root rot, leaf spot, and powdery mildew.
Alocasia x Amazonica is one of the popular varieties of the Alocasia species. This is because of its very large foliage and its sharp leafy edges. It is a hybrid cross between two unverified parents from the southeastern part of Asia.
All varieties of the Alocasia family all suffer from similar diseases and are often attacked by the same kind of pests. So all solutions to the problems of alocasia amazonica apply to the other varieties of the plant including popular hoursplants such as Alocacia zebrina, Alocacia cuprea and Alocacia wentii – to name just a few
Diseases
Taro Leaf Blight (Phytophthora colocasiae)
This disease is caused by a fungus called Phytophthora colocasiae. This is a waterborne disease i.e a disease that is caused by organisms present in contaminated water.
It affects the leaves, stems, and blooms of the Alocasia Amazonica plants.
In the early stages, the fungus usually leaves behind a trail of white powdery patches on the leaves, stems, and blooms of the alocasia Amazonica plants. Later, tiny patches of yellowish fluid can form that turn purple when dry.
This disease thrives well in a warm climate and also in spaces with poor air flow and ventilation. Prevention is better than cure, so ensure that the optimal growing conditions are provided to reduce the chances of a serious infection taking hold.
Ensure there is enough ventilation in the room, that your plant is exposed to adequate sunlight, and that you remove infected or dead foliage carefully and promptly. Also, sanitize your shears to prevent spreading the disease to neighboring plants.
Crown, Stem, And Root Rot (Pythium Rot)
Pythium Rot (Rot of Crown, Stem and Root)
This disease is caused by a Pythium parasite found in contaminated water used for irrigation and watering. It is propagated through water logged in the soil. It strives in wet soil without a proper draining system.
This parasite attacks the root and stem of the alocasia Amazonica plants causing them to rot beneath the soil. If it is not diagnosed early, it can sometimes spread to the crown of the plant.
At the early stage, the best way to diagnose this problem is by looking at the soil line to check for any change in soil color and scent.
If the parasite continues to spread undetected, the plant might stop sprouting new leaves and experience stunt growth.
Another way to check for rot in the root of the plant is by gently grabbing the stem and pulling it upwards and downwards with care. If the plant feels strong in the pot without shaking, then it’s likely not affected by the phylum parasite. But if it wiggles with ease, then it is assumed that the root is weakened as a result of rot.
Trim off the dead and infected foliage and repot into new growing medium. This may not always be successful but repotting may sometimes save your Alocasia plant.
Leaf Spot (Phyllosticta Spot)
Leaf spot disease is the least threatening among all 3 diseases discussed. It only affects the leaves of the plant by causing lesions on the surface of the leaves. This is another fungal issue that can arrive via contaminated water.
It turns the infected section of the plant foliage brown and if it’s not treated early, the most that will happen is the leaves fall off and the plant looks a little unhealthy.
Separate the infected plants from any other plant to The spread of this issue, and remove any affected foliage promptly. In severe cases, an organic fungicide may be applied.
Pests
Leafminers
Leafminers refer to the larvae of various pests such as moths, beetles, fleas, etc. They appear when adult pests lay their eggs on the plant leaves which then transform into larvae.
They are not harmful but they do leave a trail of spots on the leaves
This can be handled by fending off other adult Pests from your plants to prevent them from laying their eggs and also using insecticidal soap when necessary to kill them off.
Spider Mites
Spider mites are a common pest of alocasia amazonica. They are tiny and almost invincible to the naked eyes. They attack the leaves of the plants and leave behind a trail of spots, discoloration, and patches.
If not detected and treated at an early stage, the infected leaves will wither and fall off.
Water well and maintain sufficient humidity to reduce changes of infestation,.
Whiteflies
Whiteflies are sap-sucking insects that cause the leaves of the alocasia Amazonica Plants to turn yellow, dry off, and then fall off.
Also, whiteflies can attract other insects such as ants to the plant as a result of the sweet substance created during the sap-sucking process.
Use organic sprays or traps where absolutely necessary to keep a serious infestation at bay. Though often you may simply be able to wipe these off the plants.
Aphids
Aphids are also sap-sucking insects that often cluster beneath leaves and release a sticky substance that can attract ants to the plant.
Again, Use organic sprays or traps where absolutely necessary to keep a serious infestation at bay. Though often you may simply be able to wipe these off the plants.
Scale
These are usually small round brown lumps on the leaves and stem of the plant. They often appear in different shapes, sizes, and colors.
As when dealing with whiteflies and aphids, you can simply wipe or wash scale insects off the plants.
