To provide a contrast of shapes in your garden, you need some plants that mound and some that send up vertical spires. Tall spires of bell shaped flowers are produced by foxgloves, which belong to the genus "digitalis." The chemicals from these plants have been used to treat heart disease. The name "foxglove" seems to have evolved from "folk's glove." Folks referred to "little people" or "fairies."
There was an ancient superstition that if you picked a foxglove you would offend the "fairies." Most varieties are biennial, flowering in the second year after planting and then dying out. However, they frequently self seed and there are a few true perennial foxgloves available.
All varieties like partial shade and rich well drained soil with plenty of moisture. They like a mulch to protect their roots over the winter. The blooms open progressively up the stem with the open flowers at the bottom and the buds at the top. Many of the flowers have interesting dark colored spots that create an exotic effect.
After the blooms fade, leave the spikes to set seeds if you want them to reproduce. Foxgloves are lovely to look at, but they are poisonous, so if you have young children, you might want just to admire them in someone else's garden.