Cerise to magenta-purple. Dahlia Marcel Dassault is a vibrant decorative dahlia with dark green-purple foliage that shows the dahlia to perfection. Cottage garden favourites dahlias provide months of cut flowers and colour in the summer garden, mix with purple, maroon, orange, pinks and greens. They work particularly well planted with asters, nepeta, echinacea, galtonias, Eryngium and other hardy perennial plants