Sisters at Heart has two leaves affected by black spot, so it's off the list of "naturally resistant" roses, and the list is now down to 22.
Andi, my Carefree Celebration also has no resistance whatsoever. In general, the Radler roses (Knockouts, double Knockouts, etc.) are a real disappointment in this area.
Carefree Delight and Carefree Spirit, however, are Meilland roses and they haven't shown a trace of black spot yet, although Carefree Wonder, another Meilland rose, is not resistant at all.
