Corn kernels dry
New Jersey in sandy soft soil. Water every day 30 minutes or more. Planted deep 2 to 3 inches (4 rows), 36 plants 1 to 2 seeds each plant. The plants when fully tall look green. The corn comes out long and thin with kernels dried up inside, no plumpness and no juice. Looks like the corn you sell at Halloween (inside). Fertilize several times. What am I doing wrong? Tried different areas, same problem last 4 years. Buy one variety - White.
First, they may not be getting enough water. While you are watering plenty, you may be over and under watering at the same time. Since you water daily, the plants won't grow deeper roots. The roots will stay shallow. But, because you have sandy soil, the water filters away deeper rather quickly. Since the corn does not have deep roots, it won't reach where the water is and will act under watered. I would recommend adding lots of organic material to your corn bed. This will help hold the water nearer to the soil surface longer. I would also change how you water to 1-2 times per week for a long period. This will encourage deeper roots.
Second, you may have a pollination issue. While you are planting correctly for pollination, things like humidity, harsh sun or insects that attack the silks during the pollinating process, can greatly reduce pollination rates. You may want to try hand pollinating to see if that help. This article will help with that: https://www.gardeningknowhow.com/edible/vegetables/corn/corn-pollination-how-to-hand-pollinate-corn.htm
Third, is unlikely, but possible if you were planting from the same seeds. You may have bought seeds for dent corn (dent corn is what you feed animals and is what you use for decoration in the fall. It is called dent corn because it gets a dent in the top of the kernel) that were mislabeled as sweet corn. But, if you have bought new seeds every year, this would not be possible.
You may also want to try another variety. If you contact your local extension office, they will be happy to recommend a corn variety that does well in your specific area.