I had a customer come by with a leaf on her old established rose bush today with spotting that I have never seen before. I am positive that it was not blackspot as the spots were so uniform and precise with no halo around them. It was if they had been drawn on with a felt pen. Any ideas anyone.?Air circulation does seem to be an issue as the garden is new to her and she was afraid to get in and give them all a good pruning.I looked at a disease called purple spotting and it does seem to be cultural rather than viral but I have never seen it here on Vancouver Island B.C. Thanks now for any input. I am enjoying these forums and are finding them very useful. Jan
The early season black spots on my roses can look just as you described - well circumscribed jet black spots, uniformly round, but of different sizes, with no halo effect and no yellowing. However, invariably, these spots will go through the changes with the appearance of central pallor, yellow halo, and, finally, completely yellowing of the leaves before they drop off.
