Flowers are borne in large clusters. Each cluster contains 25 or more flowers. Harrison's Yellow' is a one-time bloomer, blooming heavily in June. No mention of hardy roses would be complete without mentioning the more than 85 rose cultivars developed by the late Griffith Buck during his tenure at Iowa State University. Dr. Buck's roses are noted for their free-flowering habit, disease resistance, and winter hardiness.
Most varieties do suffer signifi cant winter dieback.
Carefree Beauty' is Dr. Buck's most well known variety. Carefree Beauty ' blooms heavily in June, moderately through the summer. The shrub grows 4 to 5 feet tall and wide. Blue Skies' has lavender-blue flowers. The aforementioned roses are just some of the many roses that will perform well in Iowa.