Before considering phlox diseases and methods of dealing with them, you need to know about the physiological disorders of the plant, since they should be distinguished from viral and fungal diseases. As a rule, physiological damage occurs due to improper agricultural practices and the cultivation of phlox in acidic soils.
For example, leaves began to dry and fall on a plant. This is a physiological drying that begins with the lower leaves. It occurs due to lack of moisture. Phloxes simply get rid of excess surface that evaporates moisture on their own. Leaf dying occurs while drought lasts . The same process occurs due to summer or late spring plant transplants. To prevent drying out, abundant watering is needed, after transplanting - shading and regular spraying with water.
Another physiological disturbance is cracking of the stems. This occurs during the intense growth of phlox. Longitudinal cracks appear at the bottom of the stem, it becomes flat and subsequently breaks off under the weight of the inflorescence. This happens due to an excess of moisture or nitrogen, as well as due to thickening of the planting.
Phlox Disease: Photos
Phlox: diseases and pestsConsider the main diseases that affect these plants, as well as the reasons why they arise, and measures to combat them. The most dangerous are viral diseases, since the diseased plant must be removed together with the earth and destroyed.
Ring spotting is a type of phlox virus disease. In May or June, light spots with a characteristic ring pattern appear on the leaves. If the lesion is severe, then the spotting covers the plant completely. As a result, deformation and curl of the leaves occurs, and flowering does not occur. The black ring virus is carried by nematodes.
Curl (wrinkling) of the leaves. This disease causes the cucumber mosaic virus. The leaves are covered with irregular shape necrotic spots, scabs. They become lumpy and curly. Sometimes a mosaic pattern of yellow-green color occurs. The plant stops growing, the stems become deformed and brittle.
Variety also refers to phlox viral disease. It manifests itself when mass flowering occurs. Light touches appear on the flower petals and the leaves become deformed. Rosa mosaic virus is carried by nematodes.
Measures to combat viral diseases are, first of all, the identification and destruction of already affected plants. Since the disease carriers are mainly nematodes, the site should be treated with nematocides.
Fungal Phlox Disease
Rust is a very common disease that affects varieties with dark leaves and inflorescences. It appears in the form of spots of rusty-brown color. Their size and number gradually increase, the leaves dry and die. The diseased plant and the soil around it should be sprayed with iron sulfate (3% solution) or copper chloroxide (0.7% solution).
Septoria (leaf spot) also refers to fungal phlox disease. Symptoms appear in mid-June. Rounded grayish small spots form on the lower leaves. They begin to grow, then turn yellow, and a reddish border appears. As a result, the affected areas die off. For the struggle, the same solutions are used as with rust.
The main pests of phloxes include nematodes, slugs, caterpillars of cabbage whites and a scoop, drooling pennies. To combat them, the drug "Inta-Vir" is used. The paths between the plantings and the soil are dusted with ash, fluffy lime and Metaldigid.