Griffith Buck Roses were first bred by Dr. Griffith Buck around 1950 when he started combining strains of very cold hardy roses with modern hybrid teas and other roses. To ensure he bred winter-hardy plants, he tested them in harsh Iowa winters of 20-30 degrees below zero with absolutely no protection. The survivors would be the seedlings he chose to introduce. Griffith Buck Roses are very disease resistant roses and have been tested in Iowa's hot humid summers, too. While other roses need protection in zone 5, these roses do not. Some protection in Zone 4 is advisable. In order for these roses to be ready to overwinter in zones 4 and 5 they should be planted by June 15th.