Growing your own popcorn does not mean that you will immediately have a movie snack on harvest day. Depending on the variety of popcorn, it will take between 85 and 120 days to mature, according to Mother Earth News. For the popcorn to pop, you must dry it to 13 to 14 percent moisture, according to Iowa State University Extension Office. This can be done either artificially or naturally, depending on your local climate conditions. Allow the popcorn cobs to remain on the stalk as long as possible until the kernels and husks appear dry, but pick the corn and dry it artificially if rain threatens.
Remove the husks from the popcorn cobs, then place the cobs into mesh bags.
Hang the bags in a dry place, below 130 degrees Fahrenheit, for several weeks until the popcorn kernels appear shriveled. The amount of time will depend on the humidity levels in your climate.
Push several kernels off the cob with your thumb and pop them in a popcorn popper to test the moisture content. Shell the remaining popcorn cobs if the kernels pop properly, but leave the other cobs to continue drying if the popcorn does not pop or sticks to the inside of the popper.
Shell the dried popcorn kernels with a popcorn sheller or push the kernels off with your thumb. You can refrigerate the popcorn in an airtight container for up to 30 months.
Preheat the oven to 300 degrees Fahrenheit.
Remove the husks from the popcorn cobs. Push the kernels of corn off each cob with your thumb. Alternatively, use a popcorn sheller (available from farmer supply stores and via the Internet). Discard the cobs.
Arrange the popcorn kernels in a single layer in a large roasting pan, then place the pan in the oven. Turn down the oven to the lowest temperature setting.
Dry the popcorn for five hours. Stir it every hour.
Turn off the oven and leave the popcorn overnight. You can pop the the kernels right away or refrigerate it in an airtight container for up to 30 months.