What medicine works well to prevent and treat black spot disease on roses?

Roses are very beautiful, but they are also prone to disease. If roses are planted outdoors, once they get rained on they easily develop black spot disease, so what medicine should be used when roses get black spot disease?

To treat roses infected with black spot disease, you can use DuPont Fuxing (DuPont Star) plus zineb: remove all the diseased leaves of the rose, then spray the remaining leaves several times on both sides. Black spot disease is a common fungal disease of roses, mainly caused by rain, and normally keeping roses from being rained on can effectively prevent black spot disease in roses.

1. Other chemical control

1. Besides DuPont Fuxing (DuPont Star) and zineb, the main medicines for roses also include Trichoderma harzianum; regularly inoculating with Trichoderma harzianum, which fights harmful fungi, can also prevent black spot disease;

2. Regularly spraying thiophanate-methyl, giving roses more ventilation and sunlight, can also reduce the chance of roses developing black spot disease.

2. Physical control

If roses are planted outdoors, to guard against black spot disease the best method is to avoid rain: you can lay down plastic film when it rains, or build a simple rain shelter. If rain truly cannot be avoided, then right after the rain you should spray the roses at the first opportunity, which can also effectively prevent roses from getting black spot disease.