Broomcorn (Sorghum vulgare) is not actually corn, but is instead related to the sorghums used for grain and syrup (Sorghum bicolor). Broomcorn has a coarse, fibrous seed head that has been used to make various types of brooms and brushes for several hundred years.
While there are still artisans creating these natural brooms today, this crop is now more commonly used to make decorative items, such as wreaths, swags, floral arrangements, baskets, and autumn displays. It takes about 60 sprays (heads) to make a broom, but wreaths and dried arrangements require only a few plants. Broomcorn is available in natural colors, as well as purple and various fall colors.
While not a traditional crop in the west, broomcorn will grow and mature a crop here easily. For detailed instructions, this publication can help.
Making a Broom from Broomcorn
This video will show you how to make a very basic broom and these instructions are for another type of broom.