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Black spot
Wills
Posts: 262
Hi folks is this black spot on my rose bush if it is which is the best treatment.
0
Wills
Posts: 262
Posts
Looks more like downy mildew, which has been a problem with humid conditions this summer. Keeping the rose healthy - well fed and watered, are the important things through the growing season. That way it can fight off fungal infection. Important NOW is to remove all those leaves, even half cut back the rose to do it and dispose of them so that the spores are removed. Pick up any fallen leaves, too and dispose. No point now in spraying (I don't anyway, as I'm against the use of chemicals, but if you don't mind using a fungicide, then start in spring at bud burst and keep up the regime, following the directions.) Don't do as they do at David Austin Roses and spray twice a week to make sure their stock looks healthy. Roses grown like that may look good, but grow 'soft' and when they come out of the nursery situation they haven't the natural resistance to all the bugs and diseases and can be quickly overcome.
H-C