Unlike sweetcorn, which is prized for its tender kernels, ornamental corn and popcorn are harvested when hard and dry. Popcorn only pops once the kernels have dried, and ornamental corns are prized for their colourful dried kernels. Most of the drying occurs in the field before harvesting, but some further drying is necessary so the corn won't rot or get mouldy. Proper harvesting and drying of the corn on the cob provides for the longest storage life.
Harvest the corn cobs after the husks turn dry and brown. Bend the ear down toward the stalk, breaking it free with a twisting motion.
Peel back the husks from the corn ears. Cut the husks off at the base or leave them attached for ornamental purposes.
Spread the ears of corn in a single layer on a large screen. Set the screen up on bricks or sawhorses so air can circulate freely around the corn.
Dry the corn in a warm, well-ventilated area for seven days. Turn the cobs daily so all sides dry evenly.
Press your fingernail into the corn kernels. Fully dried corn is hard and won't dent. Dry for an additional three to five days if your nail leaves an imprint in the kernel.
Store popcorn cobs in an airtight container in a dry pantry until you are ready to use them.