Disease
Prevent disease and nutritional exhaustion of the soil by using 4-year crop rotation and composting old stalks.
Pests
Wireworms are a pest in home gardens and may burrow into the seeds. Loopers are pale olive-green caterpillars up to 2.5cm (1″) long. They chew into the centre of young corn plants and can kill the plant if the growing tip is damaged. Seed corn maggot is a small, legless maggot that attacks germinating seed. Planting in warm soil or using predatory nematodes may help prevent seed-destroying soil creatures.
Companion Planting
Corn is a good companion to beans, beets, cucumber, dill, melons, parsley, peas, potato, soya beans, squash, and sunflower. Avoid planting next to celery or tomatoes. Amaranth makes a great mulch between rows by competing with weeds and conserving ground moisture.