Harvesting your own seed corn at the end of the growing season can save you a great deal of money on next year's bounty. Another advantage of raising corn from seed you saved is that the plants that produced the seeds are already acclimated to your location. Harvesting your own seed corn is really not much more involved than harvesting eating ears, and the payoff is well worth the little bit of extra effort. Seed corn is ready to harvest about four to six weeks after ears have reached the eating stage.
Choose the nicest ears of corn when the crop is fully ripe and has reached readiness for the table. You'll want the earliest developing, plumpest mature cobs to save for seed. Pick the other ears from the plants.
Cover the seed corn ear with a brown paper bag, and secure it in place with a piece of string. This will help protect the seed corn from marauding insects, crows and grubs, and from dropping on the ground. Leave the cob to dry out on the plant as long as you can, with four to six weeks being optimum.
Pull the cob from the plant, with the bag still in place. The husk should be completely brown and dried by now. Take it indoors and remove the bag. Pull the husking back from the kernels, and hang the ear upside down in a cool, dry location. Keep an eye out for rodents, and be prepared to move the corn if necessary.
Check the ear a couple of times each week. Rub your fingers over a few kernels. If they pop right off, the seed corn is ready to store.
Twist the dried corncob between your hands to break the kernels from it. Label brown paper bags and store the seed corn in them. They'll keep just fine in the vegetable crisper of your refrigerator until you're ready to plant in the spring. They'll be good for at least two years. Toss the cobs onto your compost heap.