I live on the east coast of Fl. in zone 9. For the life of me I can't get corn to grow. I start it in pots, it comes up quick, transfer it to a grow box, and then it dies. This summer I finally got tassels and corn came out on the stalks and died. Also frustating, is when the corn gets say a foot high and something eats the leaves with small thin holes. I have it in pots now, it is tasseling but this is where the problem starts. Soil is decent soil from Lowes with a good pH.
Certified GKH Gardening Expert
Corn doesn't transplant well, so you may want to start with just direct planting the seeds so that the roots system is stronger.
As you are growing in containers, I would also recommend that you increase water, especially after it starts tasseling. If the container has proper drainage, you should be watering at least once a day and at least 2X a day if the temps get up over 85F.
The holes may be caused by slugs. This article will help with that: