Also known as money plant, silver dollar or honesty plant, penny flower (Lunaria annua) gets its name from its fruit, which looks like a silver dollar when dried. It grows well in sun or shade, but does not suit an ornamental garden because of its weedy, invasive habit.
People usually grow penny flower plants for the fruits, which develop in the summer. The fruit looks like a flat, round seed pod that dries in late summer. Its outer covering then turns silver with a paperlike texture.
Penny flower plant grows to reach a height of 2 to 3 feet and a width of about 1 foot. Its leaves have coarse teeth on the edges and grow quickly. It also has pinkish-purple flowers that grow on terminal racemes.
People grow penny flower plants for borders and dried flower arrangements. The plant produces many seeds and often reappears every year once planted. It can become a serious weed.