How to Grow Corn
The word corn has had many meanings. Originally it meant any hard particle or grain, sand, or salt. Corned beef earned its name because it was cured with salt. Both wheat and barley once were called corn in the Old World. Maize, the main cereal of the New World, was first known as Indian corn and later just corn.
Corn supported the early civilizations of the Americas. Fossils show that corn was grown in North America more than 4,000 years ago. It was after the discovery of America that corn spread rapidly throughout the Old World.
Dent corn is the corn most widely grown by farmers. It's not sweet at maturity and has an indentation, or dent, atop each kernel. It is usually grown to feed farm animals.
Most home gardeners grow sweet corn which differs from other types of corn by its ability to produce and keep more sugar in the kernels. This characteristic is controlled by a single recessive gene called sugary-1. Other distinguishing characteristics of sweet corn include tender kernels at edible maturity, refined flavors, a tendency to produce suckers at the base of the plant and wrinkled seeds when dried. Standard sweet corn tastes best when cooked immediately after picking and remains sweet for only a few days. A variety called super sweet is even sweeter than sweet corn, it retains its sweet flavor longer, up to 14 days, because the sugar is slow to convert to starch but it needs warm soil and twice the moisture of standard sweet corn to germinate.
Popcorn resembles sweet corn, the main difference being that the kernels are pointed and explode when subjected to heat. Popcorn is grown in the same way as sweet corn.
For a continuous supply throughout the summer and into the fall, plant early, midseason, and late varieties, or plant every 2 to 3 weeks. Keep in mind that the number of days to maturity is a relative figure, varying by the total amount of heat the corn receives. Corn does not really start growing until the weather warms, and it grows best where summers are long and hot. Varieties listed as 65 days may take 80 to 90 days when planted early but may come close to the 65 days if they are planted at the specified time. When planting for a succession of harvests, the effect of a cool spring should be considered. Rather than plant every 2 weeks, make the second planting when the first one is knee-high.
Corn does not transplant well, so it should be grown from seed, sown outdoors after all danger of frost has passed and the soil temperature is 50 degrees or higher. Plant seeds 2 inches deep, 4 to 6 seeds per foot, in rows 30 to 36 inches apart. Thin to 10 to 14 inches between plants. You can crowd back to 12 inches or even 10 inches at the minimum, but, except for small-growing types, which can be spaced 8 inches apart in rows 30 inches apart, planting any closer lowers the yield and risks a crop of nubbins. Many home garden corn plantings are ruined by over crowding than any other reason, and too many seedlings in a row act just like weeds. If you over space corn you usually are compensated by more and some sucker production.
At planting time, fertilize in bands on both sides of row of seed, 2 inches from the seed furrow and an inch deeper than the seed level. Use about 3 pounds of 5-10-10 in each band per 100 feet of row. When the corn reaches 8 inches high, side dress with the same amount. Repeat again when the corn reaches 18 inches. Corn needs continual watering, from planting until harvest. The water need is greatest from tassel time to picking time, when sweet corn makes very fast growth, no check in watering should happen. In very hot and dry weather, rolling of the leaves may occur in midday even when soil moisture is good, if the plants transpire water faster than the roots can absorb it. But if the leaves roll other than midday, check the soil for adequate moisture.
Corn is shallow rooted, so when weeding be careful not to damage the roots. Plants can be mulched, or pumpkins, cucumbers and squash can be implanted with the corn, in the Indian tradition.
As a general rule, corn is ready to harvest 3 weeks after the silk first appears, although this will vary depending upon the weather during that time. The silk will become dry and brown when the ears are near ripeness. Probably the only sure way to tell is to open the husk and press a kernel. If it spurts milky juice, it is at the peak of ripeness. Varieties differ, but most will produce two ears per plant. The top ear usually ripens a day or two ahead of the lower one.
Harvest by breaking the ear from the stalk, hold the ear at its base and bend downward, twisting at the same time. The idea is to break off the ear close to its base without damaging either it or the main stalk. Popcorn should be harvested at of the growing season when the stalks have turned brown. It should then be dried in a warm area before use.
Some do's and don'ts....corn is wind-pollinated....
To make sure of pollination plant in short blocks of 3 or 4 rows rather than a single long row of the same number of plants. Don't interplant different types of corn. Pollen from dent corn will make sweet corn kernels starchy and less sweet. popcorn will cross-pollinate with the sweet corn unless it's more than 100 feet away. Yellow hybrid corn must be planted downwind from white corn or the white corn will not develop.Standard sweet varieties will reduce the quality of the supersweet kinds. Grow the supersweet at least 300 to 400 yards away from standard types. One way to avoid cross-pollination between different types of corn is to wait about 4 weeks between plantings to ensure that the plants will not be pollinating at the same time, another way is to plant them in separate areas.
Don't worry about suckers. They don't take any strength from the main stalk, and removing them may actually reduce yield. Do look out for the corn earworm. its eggs hatch on the silk of the developing ear and larvae burrow into feed on the kernels. Ears with tight husks and good tip covers are somewhat more resistant to corn earworm damage. They do not prevent the entrance of the worms but the damage will be lessened. Frequently, some control measure for corn earworms is necessary. Tight husks have an advantage over another pest, birds, which eat the kernels on the tips of the ear. The damage is worse on ears with loose husks. Such damage on the ornamental Indian corn makes it worthless. One way to solve the problem is to slip a paper bag over each ear after it has been pollinated.