To be classified as a hardy shrub rose, the plant must be able to reliably survive the Winter without any special protection. Depending on the severity of the Winter and the specific variety of shrub rose, Winter damage might be as minimal as a few dead tips on branches or as severe as the canes dying back to the ground. All roses should be grown where they will receive full sun. Planting them where they will receive good air circulation, too, will help avoid disease problems. As a group, hardy shrub roses are more disease resistant than non-hardy roses.
Some specific varieties are more resistant than others.
All roses are susceptible to the same insect pests. The first Winter after they are planted, hardy shrub roses should be mulched heavily with leaves just before it snows. After they are well established, mulching with leaves is optional. They do not require the extra protection of rose cones or tipping and will not need to be pruned until Spring. After the snow melts, look at the canes to determine how much Winter damage they have sustained.