Just for kicks, I saved last years ears of decorative Indian corn and planted some this year. Most of the ears are pretty small/underdeveloped but the stalks are the tallest corn I've ever raised. This is my 4 year old granddaughter standing next to it for scale. I'm 6'2" and I had to reach up with one hand and bend the stalk over on a few of them to reach the ears. I'd bet some of these are pushing 14 feet!