Broom corn (Sorghum vulgare or Sorghum bicolor var. technicum) is a grass grown for its long, fibrous tassels, or “brush,” used to make traditional brooms and crafts. It is a member of the sorghum family, not a true corn (Zea mays), and is tolerant of heat and drought, making it adaptable to many climates. Cultivating high-quality broom corn requires attention to detail from planting through harvest, ensuring the fibers develop the straightness and pliability necessary for a superior sweeping tool. This guide walks through the entire process, from preparing the soil to properly curing the harvested brush.
Preparing the Planting Site and Sowing Seeds
Successful broom corn production begins with proper site selection, favoring a location that receives full sun throughout the day. The soil should be well-drained, deep, and fertile; although the plant will grow in poorer soils, the best quality brush is produced in rich, loamy conditions. Before planting, the soil needs preparation, often involving deep tilling to remove debris and achieve a fine, mealy texture.
It is highly beneficial to amend the planting area with generous amounts of organic matter, such as well-aged manure, before sowing, as broom corn has high fertility requirements. Planting must wait until after the last spring frost, as the crop is sensitive to cold, and the soil temperature should be consistently warm, ideally between 60°F and 70°F. Seeds are typically direct-sown to a shallow depth of about one-quarter to one-half inch.
For large-scale cultivation or for plants intended to produce robust brush, sow seeds about two inches apart in rows spaced 18 to 36 inches apart. Once the seedlings reach approximately four inches in height, they should be thinned to a final spacing of eight to twelve inches between plants. Wider spacing encourages thicker stalks, while closer spacing can result in more numerous, smaller tassels.
Mid-Season Care and Growth Management
Broom corn tolerates dry conditions, but consistent moisture is necessary to develop long, pliable fibers. Plants require 1 to 1.5 inches of water per week, especially during dry spells. Water can be supplied through rainfall or supplemental irrigation, ensuring the soil remains moist but never waterlogged to prevent root issues.
Weeding is most important early in the season because young broom corn plants grow slowly and can be easily overtaken by competing vegetation. Once the stalks grow taller, they outcompete most weeds, but applying mulch helps suppress growth and conserve soil moisture. Standard varieties reach heights of 6 to 15 feet, and the stalks may need support, especially in windy areas.
While generally robust, the plant can occasionally suffer from fungal diseases like rust, which appear as dark red blemishes on the leaves. Providing adequate airflow and, if necessary, applying a copper fungicide can help manage such issues. The main challenge is often protecting the developing seed heads from birds, who are attracted to the ripening seeds.
Timing the Harvest and Cutting the Stalks
The quality of the final brush depends on harvesting within a narrow window of maturity. Harvesting too early results in weak, immature fibers, while harvesting too late yields brittle, discolored brush. The optimal time to cut is when the seeds are in the “soft dough” stage and the brush is fully formed but has not yet turned red or brown.
A visual indicator is the color of the peduncle (the stem supporting the brush), which should be entirely pale yellow to light green down to the base. Harvesting must occur before the brush turns red and becomes less flexible, a transition that can happen quickly. Once the ideal color is observed, the traditional technique of “tabling” or “kinking” the stalks is performed several days before the final cut.
Tabling involves walking down the rows and sharply bending the stalks about two to three feet from the ground, folding them diagonally across the adjacent row. This action serves two purposes: it prevents the brush from bending or curling as it dries, ensuring straight fibers, and it allows the heads to continue drying while still attached to the stalk. After a few days of tabling, the brush is cut off with a sharp knife or machete, leaving an eight-inch portion of the stalk attached to the head.
Curing and Storing the Brush
After the stalks are cut from the field, the process of curing, or drying, is essential to preserve the fibers and prevent mildew. The brush must be dried in a well-ventilated, shaded location, as direct sunlight can bleach the fibers and weaken their structure. Curing is often done by laying the brush in thin layers on slatted shelves or by hanging small bundles.
During this drying phase, which can take 10 to 20 days, it is necessary to ensure the brush remains straight. Hanging the bundles with the fibers pointing downward utilizes gravity to help maintain straightness, or the brush can be clamped flat during the process. Once the brush is thoroughly dry, feeling firm and snapping easily when bent, the seeds are typically removed by combing or stripping them off.
The finished, cured brush should be stored in a cool, dry environment, protected from moisture and pests like rodents. Proper storage ensures the material remains pliable and mold-free until it is ready to be bundled into brooms. Maintaining straightness and vibrant color during harvest and curing is essential for the final product quality.