[Lardman]

Is there anything I can do ? A number of the roses at mother lard's have it really badly. Ideally not the £8 a pint premixed sprays as I'll be there all day.

I do have some neem oil but will it treat as well as prevent (are we still not allowed to talk about that?)

[mumofstig]

My roses are realy bad after all the rain  I must get a spray.

This site says neem oil or baking soda
http://www.gardeningknowhow.com/ornamental/flowers/roses/black-spot-roses.htm

[JayG]

I've found Roseclear does a pretty good job of helping to prevent bad outbreaks, but not much good at 'curing' it once your roses have really succumbed, although to be fair nothing else I've tried does either.

It's not too expensive if you buy the concentrate and mix it up yourself.

Infected leaves should be picked off and binned as soon as they become loose - hopefully any new growth will stay healthy if sprayed regularly.

[DanielCoffey]

Have you tried Sulphur Rose? It is powdered flowers of sulphur that you mix with water and put through the watering can rose attachment. Harrod sell it so as a forum member you would qualify for the discount.

It does make your watering can a bit stinky but it should help acidify the leaves and topsoil.

[mumofstig]

I thought flowers of Sulphur was banned a couple of years ago 

[DanielCoffey]

Hmm... you may be right. HH have it as no longer available. I wonder if there is a news post about it?

EDIT : It looks like it might have been Lime Sulphur that was banned, not Sulphur Rose. Plenty of reputable places still seem to stock Sulphur Rose and the pellets too.

[Lardman]

Shame I put all the flowers of sulphur on the blueberry bed     I assume the sulphur rose just has extra stuff in it besides sulphur ?

[DanielCoffey]

It seems that, like other brands of "wettable sulphur", it is just powdered sulphur.

"Wettable sulphur is a fine colloidal form of elemental sulphur which is soluble and provides a high degree of control on powdery mildew, scab, rust and mites."

[Lardman]

I'll grab a packet I think and give it a go, Im not overly concerned about the smell - I've been feeding them comfrey anyway