How To Recognize Pelargonium Diseases?

2024 Author: Gavin MacAdam | [email protected]. Last modified: 2023-12-16 13:38

With what pleasure we admire the luxurious flowering of the beauty of pelargonium and how we begin to worry when she is struck by various diseases! In order to always be on the alert, it is important to know about the attacks of which ailments this wonderful plant is susceptible to and how they manifest themselves on its various parts. This will allow not only to make the correct "diagnosis", but also to start high-quality treatment in a timely manner

Alternaria

On the surfaces of the leaf blades of fine pelargonium (and especially on their edges), as well as on its petioles, brownish specks with fairly light centers begin to appear. Sometimes the specks can differ in a concentric structure. And with high humidity, they quickly become covered with a dark velvety coating. The flowers of zonal pelargonium are most affected by this infection. The infection can persist for a long time in the soil, continuing to infect plants. Especially often they get it when the weather is warm and humid.

Gray rot

The aboveground parts of pelargonium begin to gradually become covered with characteristic brownish specks. In this case, the lower leaves are most affected, since they are located in close proximity to the soil. And in some varieties of pelargonium, spotting on flowers also begins to develop. If the humidity of the air is noticeably increased, then the infected parts of the wonderful flowers will instantly become covered with a grayish and rather dense mushroom bloom.

Manifestations of infection on plants can often be detected after cuttings. And the pathogen can persist in the soil for one to two years. As for its distribution, in most cases it occurs with the help of water or wind, as well as with soil or infected plants.

Verticillary wilting

The very first symptoms of this disease appear in the form of a gradual yellowing of individual parts of the lower leaves. After some time, the leaves are completely covered by the infection and begin to fade quickly. At the same time, the leaves do not fall - they all continue to hang sadly on the bushes. Subsequently, yellowing reaches the leaves located above. In addition to everything, individual inflorescences with twigs may begin to fade. And if you cut infected shoots, you can easily notice a significant darkening of their conductive tissues. The particular danger of this infection is that the pathogen is able to persist in the soil for as long as fifteen years! And the disease can be transmitted both through rooting of cuttings and through damage to the roots.

Pelargonium is most affected by verticillium on light soils, especially if it is grown in the same place for a fairly solid period.

Rhizoctonic root and stem rot

In the lower parts of the infected stems, the appearance of dark, depressed specks can be observed. Slowly, the lesions begin to move upward, but they rarely rise to a height of more than twenty-five centimeters. Also, a grayish-whitish mushroom mycelium gradually appears on the spots. After a while, pelargonium withers sharply.

The development of rot can easily be provoked by a lack of lighting, poor ventilation, waterlogging of the substrate, keeping plants in too warm conditions, excess fertilizer in the soil and a difference in air temperature and soil temperature exceeding the range of six to eight degrees.

Rust

The upper sides of the pelargonium leaf blades begin to become covered with yellowish specks with fairly clear boundaries. And on the undersides of the leaves, you can see the formation of numerous brownish pustules, often located concentrically. The diseased leaves dry out rather quickly and immediately fly around from the flower bushes.