Black spot (Diplocorpon Rosae) is a fungus that manifests itself on Rose Bushes as black spots fringed with yellow rings on both sides of the leaves.
As the disease spreads the entire leaf goes from green to yellow and drops to the ground if unchecked black spot can affect the entire rose garden leaving the appearance of many bare-naked plants.
Sulphur is a natural enemy of black spot and powdery mildew on roses. It is common knowledge and in the public domain, that these diseases were less common when sulphur dioxide was emitted by coal fires and industrial pollution prior to the 1968 Clean Air Act.
Prevention is better than cure! In early spring, rose plants should be sprayed thoroughly with Sulphur Rose, once sprayed the fungal spores cannot germinate in the sulphur film (Sulphur Rose) and therefore cannot get a chance to attack the plant. During the flowering season roses should be sprayed every month, if heavy rainfall sulphur rose should be reapplied.
Alasdair DowlingJul 30, 2020, 09:43Can appreciate the effectveness of the use of sulphur on roses, but at £17.50 for treating 20 roses is extremely expensive, taking into account I have over 300 bushes, so need something more economical. Been using Chronos from South Africa. Maybe I'll just stick to my old remedy of skimmed milk and water. I really need a commercial quantity.Greenacres DirectAug 25, 2020, 09:41Dear Mr Dowling
Thank you for the review, Sulphur Rose priced at £17.50 treats 20 roses for the complete year which equates to £0.875 per rose bush. Rose bushes are very expensive so to maintaining them to a high standard a quality product that works is required - would you put a poor quality oil in a Rolls Royce?.
If you have a large amount of roses i.e 300+ please give us a call and we can supply in bulk - as we do with our rose wholesalers/growers