The reasons for the appearance of various spots on the leaves of alocasia and how to deal with it
Numerous types of alocasia, actively grown as indoor plants, attract the attention of flower growers due to their unusual large foliage. Healthy bright leaf plates undoubtedly delight the amateur grower. But what to do if spots appear on a green native of the tropics, the leaves of alocasia turn yellow, dry or completely fall off?
The spots appearing on the alocasia, the change in the color of the foliage and its drying out are alarming signals that the plant sends to its owner, talking about ill health and some problems. Most often, flower growers have to deal with the fact that they themselves are to blame for the loss of the attractiveness of the plant:
- The main reason for drying and falling leaves is illiterate or insufficient care of a tropical plant..
- Alocasia diseases requiring urgent treatment are in second place in terms of prevalence..
- And insect pests are slightly less dangerous.
Maintenance errors leading to alocasia stains and loss of foliage
When organizing the care of your favorite species and variety of alocasia, you need to remember that these plants in nature live in regions with a warm, humid climate. They are not aware of drafts and frosts, and the lack of moisture for this culture is simply destructive..
So that the plant does not feel discomfort, and the leaves of alocasia do not turn yellow and do not turn black in the conditions of a city apartment, an atmosphere is organized for the plant that is closest to the natural environment..
While it is not difficult to maintain the temperature in the room in the range of 18–26 ° C, it is rather difficult to create the air humidity necessary for growing alocasia. It is not always possible for flower growers to protect plants from the effects of the cold wind and to choose alocasia a convenient place in partial shade.
Lovers of indoor plants who have certain types of tropical crops in their collections often complain that the tips of the leaves dry on alocasia. Sometimes necrosis extends to the entire edge of the leaf plate, and then captures the leaf completely. Such phenomena in most cases are signals:
- excessive lighting that burns the sheet plates;
- about unacceptable temperature fluctuations;
- about dry air in the room;
- about a small amount of moisture supplied with irrigation;
- about the root decay that began due to stagnant water.
Having paid attention to the condition of the plant in time, having analyzed the conditions in which it is located, it is possible to quite accurately determine the cause of the drying or yellowing leaves of alocasia.
For example, drying of the edges of the leaf and the appearance of brown spots may indicate too dry air in the room. When it is possible to bring the humidity to the required 60–65%, the spread of stains stops, and the tips of the leaves of alocasia do not dry out. Similar symptoms can be seen if the plant is in direct sunlight or near heating appliances. But the flow of cold air sometimes causes the spread of dark brown or black spots on the leaf plate..
Sometimes, with discomfort, alocasia sheds all the leaves. If the florist notices this behavior of the plant, he should pay attention to the condition of the root system and the aerial part of the alocasia..
This reaction is possible in two situations:
- if necessary, transplanting a rapidly growing plant;
- on the eve of flowering.
In the first case, a larger pot is selected for the plant and transferred to a new substrate, and in the second, it is better to relieve a very emaciated alocasia from the additional load and cut out the peduncle that has appeared, without waiting for flowering.
Interestingly, alocasia can react in a similar way to the unbalanced mineral composition of the soil..
- If it is poor in nutrients, the grower will notice how the tips of the leaves dry on alocasia..
- With a lack of nitrogen, growth slows down, the lower leaves of alocasia turn yellow and wither.
- Unjustifiably frequent feeding causes increased foliage growth, although its shape may differ from healthy.
If you do not take measures in time and do not take care of the flower, alocasia becomes an easy prey for pests and pathogens..
Diseases of alocasia and their treatment
The composition of the soil and its moisture have a great influence on the health of the plant. If the soil mixture is too dense, accumulates a lot of moisture, you can expect that this will affect the root system of a tropical inhabitant and the quality of its foliage..
Root and stem rot are the most common diseases of alocasia, and the treatment of diseases caused by bacteria, viruses and fungi must be carried out systematically and immediately..
Fusarium and late blight on alocasia plants externally appear in the form of brown putrefactive spots on the leaf petioles closer to the base, then the disease spreads to the leaf blades. Tissues change color, soften and die.
When such spots are detected on alocasia, all damaged parts of the plant are removed, be sure to check the condition of the roots, where the focus of the disease lies. The cut sites are cleaned to healthy tissue and treated with charcoal powder. The rest of the trunk is wrapped in wet sphagnum moss and placed in a container under a film. In such greenhouse conditions, with regular moistening, alocasia will be able to give new roots and prepare for planting in the ground..
The soil mixture should be disinfected, since putrefactive bacteria can be in the soil for a long time, and a weakened plant for them is the main goal.
When infected with anthracnose, the leaves of alocasia appear brown spots with a yellowish halo. As the disease progresses, the spots on the alocasia expand, and concentric circles of a dark shade become visible on the affected tissue..
The formation of yellow and black spots on the leaves of alocasia can mean infection with powdery mildew. For all such diseases, plants are carefully treated with fungicides, and also take proper care of them..
As a preventive measure, it is worth regularly removing drying leaves and not leaving fallen plant residues on the soil..
It is they who are able to become a haven for pathogens, the treatment of alocasia from which will require a lot of time and effort..
Pests of alocasia
Harmful insects on alocasia come from infected neighboring plants or from the soil. Often invisible enemies enter the house with a flower from a flower shop..
Juice-eating insects and worms weaken the plant. As a result, the leaves of alocasia turn yellow, their tips begin to dry out, and then the process develops and affects the entire surface of the leaf plates. Without proper attention and urgent measures, alocasia drops all leaves and may die..
Aphids and scale insects can be dealt with with home remedies, these pests are easily detected and just as easily destroyed..
The main danger for indoor alocasia species is mealybugs, nematodes, aphids and spider mites..
The destruction of these pests is carried out in several stages with the help of insecticides, with which both the aerial part of the plant and the soil lump are treated. If alocasia has suffered from nematodes, it is better to get rid of such a specimen, since even with vegetative propagation of the plant there is a possibility of spreading a dangerous infection.