EDIBLEharvest

Great Corn Varieties for the Home Gardener

By Barbara Melera

One of the greatest gifts that the New World presented to the Europeans was corn, or maize as it was then called by some. One of the first sights for Christopher Columbus’ crew as they reached Hispaniola was of fields of maize growing on the island. The cultivation of corn in the New World is one of the most ancient of traditions. Corn was grown from Brazil and Chile to as far north as southern Canada. It was a key ingredient in the diets of the Aztecs, the Mayans, and the Incans, and even before these civilizations appeared, corn was cultivated by prehistoric peoples of the Americas. Corn is believed to have originated from a wild grass called teosinte. The word teosinte literally means “God’s corn.” Teosinte still grows as a wild grass in Mexico, Honduras, and Guatemala. Even today, it is so genetically similar to primitive types of maize that the plants frequently cross-fertilize. Interestingly, our modern corn has become such a specialized food product that it cannot survive without cultivation by humans. There are at least six types of corn. Dent corn has kernels that have an indentation on their tops and contain soft, starchy corn under their indented tops. Flint corn has very hard kernels that are tough to grind when dried. Flour corn has soft kernels that are very easy to grind. Popcorn kernels burst open when heated. Pod corn, which is not well known and seldom grown today, produces tiny husks on which grow multicolored kernels. It is largely a curiosity and only of ornamental significance. Sweet corn, the kind with which most of us are familiar, differs from all the other types of corn because the kernels lack the ability to instantly convert sugar into starch. This is why sweet corn retains its sweet taste for a short time after it is harvested. Sweet corn is produced by isolating the plants so the recessive genes, which code for sugar and tenderness, shine through. Three recessive genes code for different kinds of sweetness and kernel toughness: SE, SU, and SH2. SU sweet corn varieties, referred to as “normal” or “standard,” contain primarily the SU gene for sweetness. This genotype of sweet corn was the primary kind available until the last century. ‘Silver Queen’ is an example. These varieties have a sugar content of about 9 percent and the sugars convert quickly into starch, which means narrow harvest windows and limited storage ability. SE sweet corn varieties are labeled “sugar-enhanced” or “sugary enhancer,” because they contain SE genes. This genotype has increased (16 to 18 percent) sugar, with more stable sugar levels than normal sugary types. It has the ability to convert sugar to starch; that just takes longer because they start with a higher level. These varieties have a good flavor and hold better than the SU genotype. However, the skin of the kernel is quite tender and care must be taken in harvesting and handling so kernels are not damaged. The SH2 corn varieties are most often referred to as “supersweet” or “shrunken-2.” These varieties possess the SH2 gene. These genotypes provide kernels with high sugar content (about

35 percent) and a crunchy—as opposed to creamy—texture. This type stores well due to a couple of characteristics: the first being that this genotype does not have the ability to convert sugar into starch. The sturdy kernel is the other reason. The kernel (pericarp) of this type is thicker than the other types, which is good because it increases the storage life and shipping capability, but bad because it can lead to consumer complaints about kernel toughness.

Favorite Corn Varieties

The following list details the history of some of the most beloved corn varieties available today.

• Heirloom Golden Bantam 8 Row Yellow Sweet Corn ‘Golden Bantam 8 Row’ (pictured on the opposite page) was introduced in 1902 by W. Atlee Burpee from a discovery made in Massachusetts. The improved strain produced longer ears with kernels of greater tenderness. ‘Golden Bantam 8 Row’ produces two or more ears per stalk. The stalks are usually 5 feet in height. It is still the standard for open-pollinated yellow sweet corn.

• Incredible Yellow Sweet Corn SE Introduced in the late 1900s, ‘Incredible’ is one of the most popular sweet corn varieties grown today because of its delicious, long-lasting flavor and tender, golden-yellow kernels. The very long ears average 9.5 inches.

• A Native American Heirloom Blue Hopi Ornamental/Meal Corn ‘Blue Hopi’ is a beautiful, purplish-blue corn that was used by Native Americans for cornmeal. Ears average 8 inches long. Kernels are rich in antioxidants.

• A Chinese Heirloom, Broom Corn Broom corn was used by prehistoric people more than 10,000 years ago. It was first cultivated in China approximately 8,000 years ago. Benjamin Franklin is credited with introducing it into the U.S. in the 1700s. It is a sorghum whose dried tassels can be used to make brooms. The 8- to 10-foot plants produce three to five stems per plant. • Heirloom Silver Queen White Sweet Corn SU ‘Silver Queen’ is perhaps the most famous of all corn varieties grown today. Introduced in 1955, the longlasting, exceptionally sweet, tender, white kernels are an American favorite. It is the standard by which all white sweet corn varieties are measured.

• A Native American Heirloom, Strawberry Popcorn Little is known about the ancient variety of ‘Strawberry Corn’ except that it is a great popping corn and has delighted children and adults for millennia. The short (4 ft.) stalks produce multiple 2- to 3-inch ears.

• Heirloom Butter and Sugar Sweet Corn SU ‘Butter & Sugar’ is a very popular, bicolor sweet corn which produces one to two, 8-inch ears per plant. Flavor is outstanding and plants are vigorous. Some consider ‘Butter and Sugar’ the best sweet corn variety available today.

Corn Planting Tips

Corn requires warm soil (65–75 degrees) to germinate and rich soil to grow. Wait until after the last frost to direct-seed and make sure that plenty of dried manure has been added to the soil several weeks before planting. Sow seeds 1 inch deep, 3–4 inches apart, in rows 30 inches apart. Thin seedlings to 6–10 inches apart. For intense backyard gardening, rows can be as close as 15 inches, but the plants will require frequent fertilization. Because corn is wind-pollinated, to maximize the number of fully developed ears, corn should be planted in beds that are nearly square. We have harvested dozens of ears of corn from tiny, but intensively gardened, beds that were 8 feet by 8 feet. Corn can be grown in containers, but it is best to try ornamental corn. Sweet corn will not be very productive and may not produce at all. If planting in containers, plant no more than 6-8 plants per 18-inch diameter container. Use the soil mix described in detail in our Harvesting History YouTube video at https://www.youtube.com/ watch?v=9SIBFuSY1Nc. Do not use prepared soil mixes.

Summer’s Delights

Summer would not be summer without two vegetables (actually fruits): tomatoes and sweet corn. Like so many of my fellow gardeners, I cannot wait to taste the first tomato and relish the sweetness of the first sweet corn. Many times, the tomato never makes it into my home, and my first corn is usually tasted, uncooked, fresh off the stalk. Yummmm! Growing corn, like growing zinnias, should be a part of every child’s summer—if only for one summer and if only in a container. Corn is very easy to grow and the seed is large enough for even a two-year-old to handle. Don’t fret if during the planting experience, your child or grandchild pauses from planting to taste a wayward earthworm. Speaking from experience, it won’t hurt them. o

Barbara Melera is president of Harvesting History (www.harvesting-history.com), a company founded in 2016 to provide horticultural and agricultural products, largely of the heirloom variety, along with garden tools and equipment.

For even more detailed instructions for growing corn in our region, see the Summer 2011 issue of Washington Gardener.