Yes, these are two different cultivars, though both originated from the same growers. Knockout roses grow to a height of up to 6 feet tall and wide and are well-suited for larger gardens. They are not as disease-resistant as Drift roses, but like them, are Knockout roses are prolific bloomers. Drift rosesare shorter and serve as a ground cover that is suited for smaller gardens. They are sturdy and easy to care for, and the flowers have a more traditional shape.