About Corn

This week’s lesson: Corn!

America’s beloved, quintessential Midwest crop is believed to have originated in Mexico over 80,000 years ago (called “maize”). Corn, beans, and squash were known as the “three sisters” by Native Americans, because they could be grown as companions; the corn growing tall to provide a stalk for the beans to grow up around, and the squash providing a ground covering to prevent weed competition. Corn comes in a variety of colors, including yellow, white, black, red, or multi-colored, and a variety of types such as popping corn (for making popcorn), feed corn (for feeding animals), and sweet corn. Certain varieties of corn have also been bred to produce many additional smaller developed ears, which are the source baby corn used as a vegetable in Asian cuisine.

How do you know when it is ready to harvest? 
Typically, each stalk will produce at least one ear of corn, sometimes two. Sweet corn ears should be picked about 20 days after the appearance of the first silk strands, when the kernels are fully formed but have not yet reached full maturity (known as the “milk stage”). The kernels will be smooth and plump, and the juice will appear milky when punctured with your thumbnail. It will only remain in this stage for less than a week, so make sure to check frequently at this point and harvest before the kernels become too tough. Corn husks should be green and have visible kernels that are plump and tightly packed on the cob. Another sign that indicate that the corn is ready to pick is when the silks dry out and turn brown. To harvest, snap off the ears by hand by pushing downward, with a quick twist.

How do you store it?
Corn is best eaten as soon as possible, within a day or two of picking, or else it will lose its sweetness. Once harvested, refrigerate corn immediately, keeping the husk in tact until you are ready to eat it. To freeze corn, blanch the whole cob (husk and silk removed) in boiling water for 3-5 min, rinse under cold water, and drain. Either remove the kernels from the cob, or pack the whole cob in a freezer bag and store in the freezer.

How do you cook it?
To prepare corn, peel off the outer husk and the stringy inner threads, called the “silk” (this step is called “shucking” the corn). Young ears can be eaten raw, but as the plant matures, the cob becomes tougher, and the kernels dry out and become difficult to chew without cooking them. Raw young corn tastes great when removed from the cob and tossed in salads or salsas. Corn can be cooked on the cob by boiling, grilling, roasting, or steaming. If boiling, don’t add anything to the water; adding salt to the water toughens corn, and adding sugar isn’t necessary because it is already sweet. Over-cooking corn can make it tough, so make sure to cook for the shortest time possible (as little as 5 minutes if boiling, 10 minutes for steaming, 15 minutes for grilling or oven roasting). When grilling or roasting, you can either keep the husks on or discard the husks and wrap in foil, and roast in a 450 degree oven, or over an open grill. Try rubbing butter and seasonings on the kernels before roasting/grilling for added flavor.


Corn gets bad press when the dangers of high fructose corn syrup are discussed, but have no fear; whole corn is a great addition to any healthy diet! Just one ear of corn contains about 3 grams of dietary fiber, 386 mg potassium, 267 IU of vitamin A, and only about 123 calories. Dietary fiber supports gut health and can help maintain a healthy weight (by making us feel fuller longer). Potassium helps maintain healthy blood pressure and hydration. Vitamin A is important for maintaining eye health. Corn, like other orange and yellow fruits and vegetables also contains beta-carotene, another eye-friendly nutrient from a vegetable we normally associate with ears! Popcorn is a great way for kids (and adults) to meet their daily fiber needs, and it is tasty too!

Emily Berg MS, RD, LDN
Swedish Covenant Hospital Clinical Dietitian


Succotash is a traditional Native American dish primarily consisting or corn and beans. This recipe calls for peas, for a nice sweet touch, but you could substitute any beans such as lima beans or black eyed peas for a more traditional version. You could also try substituting squash for okra to include all of the “three sisters” crops!

Sweet Corn Succotash
Makes 4 side dish servings

2 cups fresh green peas
1 tablespoon canola or vegetable oil
1 thick slice of bacon, finely diced
1 small onion, finely chopped
1/2 pound okra, sliced 1/2 inch thick
3 medium tomatoes—peeled, seeded and coarsely chopped
3 ears of corn, kernels cut off
Salt and freshly ground pepper
2 tablespoons unsalted butter
1/4 cup slivered basil leaves

In a large pot of boiling salted water, cook the peas until tender, 5 minutes. Drain, reserving 3/4 cup of the cooking liquid.

In a deep skillet, heat the oil. Add the bacon and cook over moderately high heat, until browned. Add the onion and cook until just softened. Add the okra and cook for 8 minutes. Add the tomatoes and corn and cook until the tomatoes break down. Add the peas with the cooking liquid and season with salt and pepper to taste. Simmer for 2 minutes. Stir in the butter and basil; serve.

Recipe source: foodandwine.com, courtesy of chef Chris Hastings