Unlike the dahlias that are grown from tubers, the 'Happy Days' series of dahlias are compact mounds of foliage and flowers, topping out around a foot tall and wide. The serrated leaves are typically dark, some almost black, making the flowers pop. 'Happy Days Bico' dahlias produce large, single petaled bi-colored flowers from late spring up until frost, and do well in sun-filled garden spots and container planters. This variety can serve as the summer color in year-round baskets or as the centerpiece for summer hanging baskets and planters.