Pollination is the culprit for undeveloped kernels. Each corn kernel has a silk attached to it. The kernel will only develop if the pollen lands on that specific silk. Each kernel needs to be pollinated in order to develop into an edible harvest.

Hand pollinating can occur within ten days of the silks emerging and continue for several days as the tassels produce more pollen.
When the tassel is full of pollen, shake the plant and watch the pollen fall onto the silks. You can also gently cut off a tassel branch and brush it across the silks. A piece of paper is another way to catch the pollen and then pour it onto the silks.

Corn is ready to harvest when the ear of corn feels “full” to the touch, and the silks are brown and drying up. If you’re not sure by looking at the silks and feeling the ear, you can check the kernels. Gently peel back the husk and take a peek. If you poke a kernel with your fingernail, it should burst with milky juice. If it is clear, they need more time.

As the corn dries on the stalk, the husk will dry and turn brown. The kernels will begin to harden and lose their juicy, plump features. Once dry, pick the corn ears from the stalk and hang them up to finish drying. When the kernels can be rubbed off of the ear by hand, they are ready to be stored in a cool, dark location to plant again another season.