I grow roses as a hobby. This year has been especially bad for black
spot because of the abundance of rain. What is the best thing to use
against black spot?

wrote:
I grow roses as a hobby. This year has been especially bad for black
spot because of the abundance of rain. What is the best thing to use
against black spot?

You cannot really "cure" black spot. I've found that Orthenex, sprayed
every couple weeks works pretty well to keep my roses clear. It will
not remove existing black spot but will check the spread. Wear eye
protection when spraying with Orthenex.

--
Henry

wrote:

I grow roses as a hobby. This year has been especially bad for black
spot because of the abundance of rain. What is the best thing to use
against black spot?

Where are you located? Take a look at the fungicides recommended
locally for blackspot. Here's a website for a nursery located in
Florida that lists of fungicides by cost, disease and danger category:

http://www.rosekinggardens.com/faqs/spray_reference.htm

Availability of some fungicides depends on what has been approved for
use in individual states. Some less toxic but very effective products
are also very expensive. So there's a broad range of options available.