Rudbeckia is a classic summer flower, fit for any cottage garden. They do well in containers but prefer to be in the ground or raised planter. These flowers are in the sunflower family, which comes as no surprise, as their daisy-like blooms resemble the structure of the sunflower. Rudbeckias come in all sorts of colors and sizes nowadays. They make an excellent cut flower, and florist swoon over their blooms.