Knock Out Roses
The hottest-selling rose today is the Knock Out, which was selected an All-American Rose in 2000 by the American Rose Society, then in 2004 their Members’ Choice Rose. This family of roses was bred to be highly disease resistant, especially against black spot, and they live up to their advertising on that score. They also require no pruning, deadheading or winter protection. They’re very drought-tolerant, AND bloom continuously from May through the first hard frost (in the Mid-Atlantic area they bloom til Christmas most years). There are lots of happy customers on the GardenWeb Forum and on Daves Garden. And here’s high praise from the Arkansas Extension Service.
There’s an interesting back story here. For years, roses were bred in low-humidity California, where most roses are disease-free, but when sold to gardeners in more humid regions, the roses performed poorly. Colder regions? Ditto — poor performance. But the Knock Out breeder — now legendary Bill Radler — did his breeding in Wisconsin. He made sure they were disease-resistant by using an overhead sprinkler in his trial gardens (to encourage fungal disease.) Then, for good measure, he ground diseased rose leaves in his kitchen blender to intentionally inoculate the plants.