With the advent of modern shrub roses such as the Knock Out series, having a rose garden doesn’t require the same weekly spray program as in days of yore. In fact, Knock Outs and their like are often marketed as no-care roses – and it’s true, they are very disease resistant and will manage to survive with little attention.  What takes down these roses over time is a lack of care, however. Although they may not get black spot, that bane of the classic tea rose, they still get pests like rose sawfly. And they benefit hugely from regular pruning, including a big cutback at the beginning of the season and regular deadheading and feeding about every 4 to 6 weeks through August.