Rose Diseases and Their Prevention and Control Methods

Rose Anthracnose

symptom

When roses are infected with anthracnose, semicircular spots will appear on the edges of the leaves, and many small black spots will appear on the spots in the later stages. When the environment is humid and the plants are too dense, the disease is likely to occur.

Anthracnose usually occurs sporadically, spreading from one leaf to the entire plant.

Prevention and treatment methods

In autumn and winter, clean the plants in time, cut off the fallen leaves and dead branches, and clean them up. Appropriately thin out branches to increase light transmittance.

When the disease occurs, spray the pesticide in time. Daconin, Carbontelene, and Benomyl can all be used. Spray after diluting with water. It is better to use several pesticides alternately.

Rose powdery mildew

symptom

Powdery mildew mainly harms leaves, petioles, leaf tips and flower buds. Irregular white powdery mildew spots will appear on adult leaves, the leaves will gradually turn brown from the tips, and the leaves will gradually fall off. White powdery spots appear on both sides of young leaves, which eventually cover the entire leaves, turning them into light gray or purple-red.

The disease is prone to occur in an environment with overly dense planting, excessive nitrogen fertilizer, poor ventilation, and insufficient sunlight.

Prevention and treatment methods

Prune in winter and cut off diseased and insect-infested branches and diseased buds. Appropriate application of phosphorus and potassium fertilizers can enhance the plant's disease resistance. Pay attention to ventilation and light transmission, and ensure that the soil is slightly moist without water accumulation.

Once the disease is discovered, spray the pesticide in time. You can choose carbendazim or triadimefon sulfur suspension, spray once a week, 3 to 4 times will be enough.