How to Use Daconil on Roses Infected with Black Spot

BY GardenTech

Will Daconil® work for Black Spot on my roses?

Yes! Black Spot is a type of disease caused by the fungus Diplocarpon rosae and Daconil® is a fungicide that controls and prevents over 65 diseases.

[If you think your roses have a disease, don’t take them to the doctor, give them Daconil]

Okay, so how do I apply Daconil® on my roses?

With ornamentals, you spray the leaves and buds to the point of runoff. For best results, begin applications as directed for each type of ornamental and disease found in the back label booklet. For roses, it is recommended you put down your first application during the spring bud break.

What is spring bud break?


What is spring bud break? Bud break is when dormant buds along the plant’s stems start to break open in spring and shoots begin to grow. Here is a picture of spring bud break on a rose. .

[Rose Spring Bud Break]

I think I am a little past that stage… I see my roses blooming.

It’s not too late to spray Daconil®. Next Spring, try to spray them during spring bud break so you won’t have to worry about Black Spot while they are blooming and beautiful.

Okay, I sprayed them. Is there anything else I should do?

You are done for today but spray them again on a 7 to 14 day schedule until conditions are no longer favorable for disease development.

[Black spot on rose leaves, Nelson 2011]

At first, I thought a bug was eating my roses! I tried an insecticide but it didn’t work so I asked around but do you know where can I get more information on common diseases?

You should reach out to professional nurseries or your local extension agent.  Extension agents are experts in Agricultural and Environmental Sciences and they love to help the public with everyday questions about gardening, pests, farming and even, fungi and diseases!  


Nelson, Scot.P1010585 Black Spot of Rose. 2011. Plants Pests and Diseases.Flickr. Web.

Daconil is a registered trademark of GB Biosciences Corp.

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