Mel, the only way to get rid of blackspot is to spray a fungicide--or learn to live with it. Spraying can get a number of posters upset, but if you want to go that direction (and I do spray occasionally in the spring and fall when temperatures are most conducive to BS formation), I recommend using the product Bayer Garden Disease Control for Roses, Flowers, and Shrubs available at Lowes or online. Make sure it is that name--Bayer puts out a number of products, most of which you probably do NOT want to use, for various reasons. You will also need to buy a small 1-2 gal. sprayer container--costs about $20 at Lowes, HD, Wal-Mart, etc. FOLLOW SAFETY DIRECTIONS CAREFULLY. And spray in the morning on a wind-less or nearly wind-less day--unless you like a sudden face full of spray from the breezes. Water the plants well the day before spraying.

There are other products out there also--in my opinion, many of them are quite ineffective.

If you ever want to expand your rose beds, I urge you to check for disease-resistant roses. Many of the popular roses from the past, such as the ones you probably inherited, are disease-magnets. Many of us gardeners today are much more health conscious when it comes to today's rose gardens.

Hope that helps.

Kate

In order for BS spores to germinate, the leaves have to be wet for six hours.

You may be able to get some control by relocating the plants so that the plants dry off quickly--morning sun is often recommended, as is spacing the plants for good airflow. BS is much less of an issue in our front yard compared to the back yard--but we aren't about to remove the understory that invites birds to our yard...

This post was edited by zack_lau on Mon, May 19, 14 at 9:38

It would be helpful to know where you are because some places have a higher black spot pressure than others. There are also different strains of black spot. Also knowing what roses they are, at least the type, helps too because some roses are more susceptible than others as well. Otherwise follow the advice above and it should get it under control.

I see it here consistently in the spring, and it's just the location, weather, and the rose's disease tolerance. I try to choose resistant varieties and still always see some when the weather is right for it.

I spray with the Bayer mentioned above, because you really don't have to spray it as a preventative like most rose fungicides. I spray after I see enough symptoms, which is a nice change from the older fungicides :) I usually only have to spray several roses in the spring, then maybe one or two roses a year when it's hotter and drier here. I don't spray for a minor case, myself, unless the rose is quite young and needs every leaf it can get.

Good luck!