Corn has a stem, which holds the ears of corn you will pick. At the top, you will see that it produces silks, (long thin shiny strings) that grow green at first, before turning a darker color as the ear ripens. Look at the corn silks; when the ear is ripe they are usually brown. Pull down the outside leaves a little and squeeze the top of the cob. If it feels soft and when you apply a fingernail to it, releases a clear liquid, leave it a few more days before picking. If it is a milky liquid and is firm, then it’s good to go. Last of all, run your fingers over the whole cob. If it feels plump and full, then pick it. The easiest way to pick a cop is to bend it away from the stem, and it usually cracks. Or just cut it off with pruning shears.