Corn seeds can be purchased from all garden stores and nurseries. Don't spend your hard-earned money on such seeds if you're already growing corn in your backyard. Given enough patience, you can dry an ear from one of your own plants and collect corn seeds from it for future sowing. With the right preparation, you won't have to buy corn seeds again.
Review the ears on your corn plant as soon as they start to mature and are ready for harvesting. Pick an ear that is the biggest and most ready for harvesting.
Slide a large paper bag over the ear of corn. The required bag size varies according to the size of the corn; it should be big enough that you can bunch the open end of the bag around the corn ear's stem.
Use a piece of twine and tie the bag's open end tightly around the stem of the ear of corn. The corn is now protected from bugs and other pests.
Let the corn dry on the stalk for as long as you can, typically until all of the other corn ears have been harvested and the stalk itself is dry and dead.
Remove the paper bag and pull the ear of corn off of the corn stalk. Hang the ear in a cool and dry room and let it dry for several more weeks to ensure complete dehydration of the corn kernels.
Hold the corn ear over a container and run your hand firmly up and down the ear. This dislodges the corn kernels into the container. Pour the kernels into another paper bag and store the seeds in a moisture-free drawer until you're ready to plant them.