Yeah, corn needs to be direct seeded because the roots start going deep right away. Once it peeks up, start weaning it off of water to force the roots to grow deeper, making better corn and a stronger plant. Water it deeply when it needs it, watering too often will stunt the stalks. In my clay soil, once a week is sufficient, even when the temps approach 100. I wait for the first signs of wilting, and then water deep. To make it wind resistant, dig a ditch about 4" deep and poke the seeds in the bottom of the ditch. As the corn grows, fill the ditch in. Our latest freeze date is May 15, so when I was growing corn I would have it in the ground by May 5.
I live in an area of truck farms, and the overwhelming favorite here is peaches and cream. One farmer plants an early variety early in an attempt to have sweet corn in the stand by the 4th of July (brings the city folks out in droves). He's successful more than half the time, even if he has to re-plant 2 or 3 times due to freezes. Trouble is, those short early varieties just aren't very good. The smart money waits until mid-July or later and buys the peaches and cream.