When to Seed Corn
Corn should be direct-seeded into the garden after your last frost date. It will germinate best in soils that are 65 degrees Fahrenheit. When deciding the best time to plant, be sure to check the days to harvest information for your variety, as many varieties need a long season.
Where to Plant Corn
Choose a spot with full sun and well-draining soil. Corn will have to be planted in a block to ensure consistent germination, rather than planting in rows like you would for other crops. You’ll have to grow at least a 3x3 block at minimum. Choose a spot where this planting method will be suitable.
Cross Pollination
Corn is one of the few crops that will cross pollinate in the first generation, meaning that they can present genetics of different corn varieties in the first season. It’s not uncommon for popcorn and sweet corn to cross, resulting in not-so-tasty sweet corn and unpoppable popcorn. For this reason, you’ll have to be mindful of what other corn is being grown by your neighbors. However, if you’d like to grow multiple varieties - no problem! Simply time them by planting them two to three weeks apart so that they are tassling (pollinating) at different times.
Growing Corn
Plant seeds ½ to one inch deep and three inches apart. Ensure that rows are at least 12 inches apart. As the seeds germinate and grow (typically once they reach four to six inches tall), they can be thinned to eight to 12 inches. Once they’re about 12 inches tall, fertilize them with a high nitrogen fertilizer.
Harvesting Corn
Harvesting corn is different depending on what type you’re growing. Sweet corn is usually ready about three weeks after the plants tassel. Keep a close eye on your corn patch as the ears grow. The harvest window for sweet corn is usually just a couple of days. Test for ripeness by peeling back the husk and puncturing a kernel with your fingernail. If the juice that comes out is white, the ear is ready! If it’s clear - it hasn’t quite reached its peak yet.
Dent, flint, and popcorn ears should be left on the plant until the husks have turned completely brown. Ideally you can leave them on the plants until they are completely dry, but if you have lots of rainy weather predicted for the late summer or early fall, it may be best to bring the ears indoors so they can dry.