Diseases and control methods of Phlox

Brown spot of Phlox

symptom

Brown spot disease mainly harms leaves, pedicels and stems. In the early stage of the disease, circular spots will appear on the leaves, gradually expanding outward, and the spots will merge into pieces, causing the leaves to dry up, and long strip-shaped spots will appear on the stems. During the flowering period, the flowers turn yellow and wither, and even a black mold layer appears.

Prevention and treatment methods

Control the humidity of the environment, ventilate frequently, and do not water directly from top to bottom when watering to avoid soaking the leaves.

Before planting, the soil and flower pots must be thoroughly disinfected, and the roots must be irrigated with methyl thiophanate solution once every half a month to effectively prevent brown spot disease.

Phlox white spot disease

symptom

White spot disease, also known as leaf spot disease, is a common wilt disease of Phlox. When the disease occurs, water-like spots appear from the bottom to the top of the plant, with a diameter of about 2 to 4 cm. As the bacteria spread, the spots will turn dark brown in the later stages.

Prevention and treatment methods

Plants should be pruned in time in autumn, and diseased leaves and plants should be removed. For those that grow weak, appropriate fertilizers can be applied to increase their disease resistance. The maintenance environment should ensure good ventilation and moderate watering, and should not be too dry or too wet.

During seedling cultivation, use potassium permanganate solution to irrigate the roots in time for disinfection and sterilization. During the outbreak period, spray Benomyl in time.

Phlox virus disease

symptom

Viral diseases are mainly spread by insects and sap. When insect infestations occur, wounds appear on the leaves, and in a relatively humid environment, they may be infected with viral diseases. When the disease occurs, the edges of the leaves will turn red and even slowly dry up. It cannot bloom normally, the flowers turn green and become deformed, and the leaves lose their luster.