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Diseases of chrysanthemums must be known from photographs in order to recognize diseases on flowers in time. Most diseases are treatable, provided they are not started too late.
Symptoms of diseases and pests in chrysanthemums
Chrysanthemums are affected by a variety of fungal diseases and pests. At the same time, the signs of illness are largely similar. If alarming symptoms appear on the shoots, leaves and flowers of a plant, then this should be a reason for the gardener to carefully examine the chrysanthemum.
You can understand that a plant has been exposed to pests or fungus by the following signs:
- yellowing and wilting - almost any disease leads to the fact that the plant’s foliage stops receiving nutrition and dries out;
- the appearance of dark dots and spots, sometimes chrysanthemum leaves become covered with spots due to a disturbance in the growing season, sometimes the dots represent fungal spores or pest larvae;
- curling and dying of foliage in the lower part of the plant, this often occurs due to root rot or nematode infection;
- the appearance of an unusual coating on the leaves and stems of a plant, for example, a spider mite leaves a light cobweb on the back of the leaf blades;
- deformation of buds and lack of flowering, this often occurs when infected with meadow bugs.
Any disease causes spots to appear on the leaves of the plant.
When the first alarming symptoms appear, it is necessary to examine the plants and determine what kind of disease they have suffered from.
Chrysanthemum diseases and their treatment
There are several main ailments that most often affect chrysanthemums. These are mainly fungal diseases, but sometimes flowers are susceptible to viruses.
Septoria
Symptoms of the disease include spots on the foliage of a flowering perennial. At first they are yellow, then gradually acquire a dark brown and black tint, grow and merge with each other. The disease spreads from the bottom up, the basal leaves of the plant are affected first. If you do not begin to treat septoria, it can lead to the complete death of the perennial.
Septoria can be recognized by yellow-brown spots
Getting rid of septoria in the early stages is quite simple. It is necessary to completely remove the affected leaves, and then treat the plant with Bordeaux mixture or copper preparations - vitriol, HOM solution.
White rust
Fungal disease has characteristic symptoms.First, lighter areas appear on the leaves, and orange spots of a powdery structure appear on the underside of the leaf blades. Over time, the disease spreads throughout the flower, the chrysanthemum weakens and begins to fade. Such a plant can no longer bloom properly.
White rust appears as powdery orange spots on the bottom and light areas on the top of the leaf.
To cure rust, you need to urgently trim off all leaves with light and orange spots. After this, you need to thin out the chrysanthemum bushes to ensure free access of air, and spray the flowerbed with Bordeaux mixture or copper sulfate. Subsequently, chrysanthemums need to be watered very carefully so that water does not fall on their leaves.
Fusarium
A fungal disease affects the root system. But the first symptoms become noticeable on the leaves, they turn yellow and brown, begin to dry out and fall off. The nutrition of the plant is disrupted, the chrysanthemum ceases to receive nutrients from the soil in the required volumes and ultimately dies.
With fusarium, the leaves become covered with dots and turn yellow.
To cure the disease, you need to remove the affected leaves and flowers. Chrysanthemum plantings are sprayed with Bordeaux mixture, and the soil is spilled with solutions that increase acidity. for example, potassium sulfate or ammonium nitrate. It is better to eliminate individual plants that have suffered too much from the disease; it is almost impossible to save a seriously affected root system.
Powdery mildew
The fungus very often affects chrysanthemums in damp and warm weather. The disease manifests itself as a recognizable coating on the leaves, whitish, ash-gray, with a powdery structure.As the disease progresses, the leaf blades begin to wither and die, the plant's vegetative processes cease, and it dies.
Powdery mildew leaves a whitish-gray coating on the foliage
You can cope with powdery mildew with standard fungicides - copper sulfate, HOM solution, the drug Fundazol helps well. Before spraying the flowerbed, it is necessary to first remove the affected leaves from the chrysanthemums, as well as completely eliminate severely affected plants.
Bacterial root cancer
The disease is classified as incurable, although it does not affect chrysanthemums very often. The most striking symptom of bacterial cancer is growths on the stems of the plant. The cancer develops quickly, the chrysanthemum not only stops blooming, but also dies completely.
Bacterial canker manifests itself as growths on the stems
If alarming signs appear, the diseased chrysanthemum must be removed entirely from the flowerbed; it is impossible to save it. The plant affected by the disease is burned, and the soil in which it grew is treated with Formalin solution. No other plants can be planted in this area for at least a month.
Chrysanthemum mosaic
One of the most dangerous diseases for chrysanthemums is viral mosaic. It is quite easy to recognize - uneven light-colored spots appear on the leaves of an infected plant. The chrysanthemum begins to grow more slowly, its flowers become smaller, and the foliage turns yellow, eventually flowering stops completely.
Mosaic stains chrysanthemum leaves and cannot be treated
It is impossible to cure mosaic disease. Affected chrysanthemums must simply be removed from the site so that the disease does not spread to neighboring plants.
Pests of chrysanthemums and their control
In addition to diseases, chrysanthemums are threatened by garden pests. There are several insects that pose a particular danger to flowers.
Leaf nematode
The most dangerous pest of chrysanthemums are nematodes - small roundworms that are difficult to see with the naked eye. They overwinter in the soil or in unharvested plant debris, and with the onset of warm weather they move to stems and leaf blades.
You can recognize the nematode by its characteristic symptoms - yellow-brown spots on the leaves, spreading from bottom to top. The spots gradually cover all the green leaf blades of the plant, merge with each other, and the affected leaves curl and fall off.
When infected with a nematode, dark spots appear on the leaves
A nematode is a pest, and when it appears, plant material must simply be destroyed. The infected chrysanthemum is removed from the flowerbed along with the adjacent soil, and the soil is thoroughly treated with insecticides, for example, Aktara.
Aphid
Aphids are a very common pest of flowering perennials. It is quite difficult to notice it from afar, but if you look closer at the leaves, small green or reddish insects will become noticeable on the back surface of the leaves.
Aphids feed on the sap of chrysanthemum leaves and shoots. If you do not fight the insect, then in just one summer, aphids can destroy all flowering perennials. The pest is not only very voracious, but also lays eggs several times per season.
Aphids can almost completely eat chrysanthemum bushes
Aphids must be controlled by spraying.If the chrysanthemums are not severely affected, then a soap or onion solution will be sufficient. In case of heavy infestation, it is better to use insecticidal chemicals - Actellik, Aktara.
Spider mite
Spider mites cause damage to chrysanthemum plantings. They usually appear in early spring and closer to autumn; it is difficult to notice them at the very beginning. But over time, symptoms become noticeable - the foliage on which the tick feeds begins to turn brown and dry out, and a light cobweb coating appears on the back of the leaves.
When spider mites appear, the leaves below are covered with a thin cobweb
The fight against spider mites comes down to spraying flower beds with insecticidal preparations or colloidal sulfur. Sanitary cleaning is important - spider mites overwinter in plant debris and lumps of soil. To prevent it from multiplying, it is necessary to clean the area and loosen the soil with the onset of autumn.
Meadow bug
The harmful insect damages all green parts of the chrysanthemum. The bug feeds on leaves, buds and blooming flowers. Under the influence of the pest, the plant stops blooming, its buds and flowers fall off, and the leaves become deformed.
The meadow bug damages buds, leaves and stems
The fight against the meadow bug consists of spraying the flower bed with insecticides - Aktellik and Aktara, Skor. For mild infections, you can use homemade solutions - soap and onion, but they do not always bring results.
Prevention of diseases and pests in chrysanthemums
Many diseases can be treated, but the easiest way is to prevent their occurrence, rather than wasting energy on fighting illnesses. Prevention of diseases in chrysanthemums comes down to several measures:
- Every autumn, the flower beds are thoroughly cleaned and all plant debris is removed. In clean areas, fungi and pests appear much less frequently.
- Flowering perennials should be watered sparingly, avoiding waterlogging of the soil. Fungal diseases develop much more readily in swampy soil.
- The soil in a flower bed should be regularly fertilized with potassium and phosphorus - these substances increase the resistance of plantings to disease.
- Every spring, plants need to be sprayed prophylactically with Bordeaux mixture three times after the start of the growing season, with breaks of 10 days.
To prevent diseases and pests from developing in a flowerbed with perennials, it is recommended to regularly loosen and weed the soil.
To prevent disease, it is important to keep the area neat and tidy.
Conclusion
Chrysanthemum diseases are easily recognized by their characteristic symptoms. With timely initiation of treatment, most ailments can be managed. If any diseases are incurable, infected chrysanthemums should be removed as quickly as possible.
