Reply
Super Contributor
Posts: 348
Registered: ‎11-06-2013

Black spot & mildew on roses

I am going back and forth on what to do. I planted mostly hybrid teas, and a few floribundas. These are bushes that I purchased locally. It is starting on my Blue Girl bushes. Not sure if I should leave it alone or treat them. I have read through the organic rose garden forum on garden web, and those people are avid non sprayers or systemic treaters. They do have some valid arguments against using chemicals. I read that the Bayer products are not for sale in New York. Wondering why? Other than the fact that they kill good bugs as well as bad bugs. (and wondering if this will start to be a trend country wide?)

I didn't research and buy disease resistant varieties. I bought what was readily available and affordable. So I have probably created my own problem. Some plants are just starting to leaf out, since they were barefoot roses in body bags. (term for bare root roses packaged in plastic bags)

Honored Contributor
Posts: 17,238
Registered: ‎03-09-2010

Re: Black spot & mildew on roses

I also live in NY and NY is one of the strictest states when it comes to banning insecticides. In short, people do not know how to read labels and apply the product the correct way. This leads to over use and it ends up in our waste streams and sewers and rivers contaminating everything in those waters. Chlordane once used against termites was a perfect example of a great insecticide which was overused by the consumer and now is banned in many states.

Bayer products used to contain imidiclopride which is now banned in NY. It was the active ingredient in product called Merit which was used for grub control in lawns. It also is high effective at getting rid of earthworms and bees! Bees are a very important pollinator for the apple industry in NY as well as pollinating other fruits for sale here.

If you purchased disease susceptible roses, then you need to be diligent with applying the fungicides on a routine basis. Some rose people switch and rotate various fungicides so the fungi do not adapt to having the same fungicide on them.

Blue Girl shrubs-- are these hollies? If you have some yellowing leaves, just remove them by hand and do not let them sit in the soil. I hope you have mulched the soil because fungus infections on plants are a splash up problem from overhead watering splashing the fungi onto the lower leaves.

Another more drastic solution is to remove the 1st 6 inches of leaves on your roses. This will help prevent or deter the splash up problem.

☼The best place to seek God is in a garden. You can dig for him there. GBShaw☼
Super Contributor
Posts: 348
Registered: ‎11-06-2013

Re: Black spot & mildew on roses

On 6/1/2014 JustJazzmom said:

I also live in NY and NY is one of the strictest states when it comes to banning insecticides. In short, people do not know how to read labels and apply the product the correct way. This leads to over use and it ends up in our waste streams and sewers and rivers contaminating everything in those waters. Chlordane once used against termites was a perfect example of a great insecticide which was overused by the consumer and now is banned in many states.

Bayer products used to contain imidiclopride which is now banned in NY. It was the active ingredient in product called Merit which was used for grub control in lawns. It also is high effective at getting rid of earthworms and bees! Bees are a very important pollinator for the apple industry in NY as well as pollinating other fruits for sale here.

If you purchased disease susceptible roses, then you need to be diligent with applying the fungicides on a routine basis. Some rose people switch and rotate various fungicides so the fungi do not adapt to having the same fungicide on them.

Blue Girl shrubs-- are these hollies? If you have some yellowing leaves, just remove them by hand and do not let them sit in the soil. I hope you have mulched the soil because fungus infections on plants are a splash up problem from overhead watering splashing the fungi onto the lower leaves.

Another more drastic solution is to remove the 1st 6 inches of leaves on your roses. This will help prevent or deter the splash up problem.

Hi JJM. It is a hybrid tea by Kordes. From what I am reading now, a real black spot magnet. I used Bayer systemic 3 in 1 a few hours ago on it. I cannot seem to find the Bayer fungus spray. Thank you for the information about what has happened in New York with people who cannot read. {#emotions_dlg.crying}

Honored Contributor
Posts: 36,457
Registered: ‎03-09-2010

Re: Black spot & mildew on roses

I just pick the leaves off and throw them in the garbage, not on the ground.

ETA: I use no chemicals in my garden, I just let the critters take care of everything, and they do!

Honored Contributor
Posts: 17,238
Registered: ‎03-09-2010

Re: Black spot & mildew on roses

I just saw the Kordes rose 'Blue Girl'. It was hybridized in 1964 and IS a blackspot magnet.

I would look for ones that received the German award that goes by the initials ADR.

These award winning Kordes roses are disease resistant.

☼The best place to seek God is in a garden. You can dig for him there. GBShaw☼
Honored Contributor
Posts: 17,238
Registered: ‎03-09-2010

Re: Black spot & mildew on roses

ADR award winners from Newflora company--http://www.newflora.net/show_roses.php?id=888

☼The best place to seek God is in a garden. You can dig for him there. GBShaw☼
Super Contributor
Posts: 348
Registered: ‎11-06-2013

Re: Black spot & mildew on roses

JJM, I put epsom salt and Rose Tone around half of my roses on Sunday. I ran out of both products, and had to get some at the store to finish. This morning, I couldn't remember if I had put epsom salt or Rose Tone around my Don Juan climbing roses on my fishpond arbors, so I did both again. Did I do the wrong thing? I suppose too much of a good thing could be a bad thing. (I think my mind is going….) either that, or I am juggling too many balls. {#emotions_dlg.rolleyes}

Respected Contributor
Posts: 2,399
Registered: ‎03-09-2010

Re: Black spot & mildew on roses

I live in the Seattle area, & finally gave up on growing roses. I've always purchased the "disease resistant" varieties, but it just doesn't matter. I do everything I'm supposed to- epsom salts, you name it....but the cooties always win. I do natural remedies for aphids, black spot, etc., & it works for a while, but then the cooties win.

I always keep the diseased leaves picked, water properly, feed properly...ugg. Today I cut down my last 2 rose trees & threw them away. I replaced them with Green Tower Boxwoods (I can shape these as they grow). I just don't want to spend the time, energy & money on a plant that is a CONSTANT fight. {#emotions_dlg.mellow}

Honored Contributor
Posts: 10,619
Registered: ‎09-22-2010

Re: Black spot & mildew on roses

On 6/3/2014 goldenretriever said:

I live in the Seattle area, & finally gave up on growing roses. I've always purchased the "disease resistant" varieties, but it just doesn't matter. I do everything I'm supposed to- epsom salts, you name it....but the cooties always win. I do natural remedies for aphids, black spot, etc., & it works for a while, but then the cooties win.

I always keep the diseased leaves picked, water properly, feed properly...ugg. Today I cut down my last 2 rose trees & threw them away. I replaced them with Green Tower Boxwoods (I can shape these as they grow). I just don't want to spend the time, energy & money on a plant that is a CONSTANT fight. {#emotions_dlg.mellow}

Your post made me laugh. I also live in the Seattle area and had roses. They are just too much work. A couple of years ago I went out and cut them all up and threw them out. I have better things to do with my time!!