Fence in your corn as the first defense against hungry deer. An electric fence helps to modify deer behavior by encouraging them to avoid the crop and keep from getting shocked. If it's a non-electric fence, make sure it's tall enough to keep deer from jumping over it and strong enough to keep them from pushing through it.
Apply repellents to your crops to keep deer from approaching. Scatter urine, such as coyote urine, around corn as a proven deer repellent. Hair is another repellent because of its odor, and the most effective and pungent hair is unwashed human hair. Remove hair from a brush, or gather it in bags after a haircut. Afterward, scatter the hair onto the plants. Apply a mixture of garlic and chili pepper to the plants; it creates a strong odor and deters the deer.
Get dogs to harass deer and keep them off the property and away from the corn. Consult local laws on unleashed dogs. Keep in mind that restrained dogs have limited usefulness.