How To Grow Corn

How To Grow Corn

How To Grow Corn

If I was asked, ‘What is your favorite vegetable?’, I think I would say it is corn. Corn is originally from Southern Mexico and the corn we eat today is believed to be a cross between two plants: maize and teosinte (a bushier plant). Corn is grown all over the world and the varieties are quite numerous. There are nine different types of corn.

White and bi-color corn recently harvested.


Blue corn was developed by the Hopi Indians, and it’s presently grown in Mexico, Arizona and New Mexico. There is a difference between the white and yellow corn we grow versus blue corn. The advantage of blue corn is that it has a higher protein content and lower glycemic index. This means that the conversion of the food to sugar occurs at a slower pace.

Corn has a number of vitamins, trace minerals and salt. It does have what some people perceive as a high carbohydrate content of six percent per ear of corn. When you take into account all the other benefits from ten percent protein, vitamins and minerals, as well as the ten percent of fiber per ear, has high antioxidant content, it’s really not a fair evaluation. To learn more about how to grow corn along with many other vegetables purchase ‘Garden the Organic Way‘

GMO, Treated Corn and F1

Most genetically modified (GMO) corn is the field corn not the sweet corn. Though Monsanto has introduced GMO sweet corn, the percentages in its usage are way less than the field corn. Don’t hesitate to ask the farmer if the corn is GMO. There are usually labels with numbers in the field that are the identifying mark of GMO corn. Look for packaging that says non-GMO corn.

F1 seed is not GMO but rather a hybrid that is usually resistant to some types of disease.

Lastly, when you buy the seed, it will say treated if it is treated. This means that some type of fungicide or the like has been applied to it.  Otherwise, the seed will be white, yellow or the natural blue for the blue corn or the true color of the popcorn that you requested. There are companies selling organic corn seed and non-hybrid seeds.

Growing Corn

Growing corn for best results is best in blocks

You need a good amount of space for the kernels to get fully pollinated and developed. Otherwise, it’s easy to grow, provided you have lots of warm weather, full sun, good fertile soil and a lot of water.

Spacing and Planting

You shouldn’t just plant one or two rows of corn. The reason is that corn is cross pollinated by wind and each kernel has to be individually pollinated in order to develop. Therefore, it should be planted in blocks or squares of at least four rows around ten feet by ten feet.

Within the row the plants should be between eight to twelve inches apart, and between rows they should be thirty to thirty-six inches apart. The seed should be one inch deep. Do not use transplants for corn.

If you add lots of compost and have a good amount of fertility, you can plant using the closer distances; otherwise, use the distance with more space.

Continuous Harvest 

Now that the space is settled, you may choose to plant multiple varieties in order to have a continuous harvest all season long. To learn about companion planting see my blog

You would start the first planting after the soil temperatures are above 65°F; in the Northeast it would be sometime in May. Corn will not germinate at temperatures below 55°F. If you want to get a jump on the season, you can cover the area with a thick layer of straw mulch in the fall. Then you can remove the straw, which may be partially frozen, and allow the soil to warm up naturally. You can also use black plastic for a week but it is not recyclable or truly organic. Either technique will increase the soil temperature. There are a few ways to stretch the growing season for corn:

  1. Plant the same variety every two weeks until the time to fully develop will begin to run into the fall. Go backwards from the time temperatures begin to drop. Let’s say it is October 15th. Working it backwards, you would plant the last crop on August 15th.
  2. Pick different varieties with different maturity dates. There are corn varieties that mature in sixty days, while others mature between a hundred to one hundred and ten, and everything in between.

Distance Between Varieties

Keep in mind that all varieties will cross pollinate with each other. Say you plant a popcorn variety with a sweet corn. These will cross, giving you a lesser sweet corn and a popcorn that will dry slower. Therefore, leave fifty feet between any given varieties if they happen to mature at the same time. If your neighbor is also growing corn, make sure you have at least this distance, as they could be growing GMO corn. This is how Monsanto was able to wipe out thousands of acres from farmers across the world, by planting their own seed corn next to their original heirloom varieties, and then claiming the seed as theirs, because Monsanto’s seed is proprietary.

Different Types of Sweet Corn

Depending on the variety, the sweetness and taste will vary lightly. Kernels of corn comes in multiple colors: white, bicolor, yellow. The sweetness of the corn varies depending on the hybridization they have gone through.

My recommendation is to plant a few varieties of corn or at least different varieties each year. A lot of the original seeds are no longer available, and I’m always concerned about using the “standard” currently grown commercially. How dependent are they on chemicals? And how prone are the popular varieties to insects and diseases?  Not having tried all these varieties, I will not comment, but rather ask you, the growers, to take note and be observant.

Fertilization and Weeding

Corn is a heavy feeder. Therefore, add lots of organic matter and composted manure; plant a cover crop, such as clover, the season before and incorporate it, followed by compost. This way, the soil will be rich in nutrients.

Once the tassels and silks appear, give it a side dressing with an organic fertilizer or some compost tea.  You may need to give it a second side dressing if you notice the leaves turning light green – this means that nitrogen is lacking. Maintain consistent moisture in order to allow the nutrients to be available to the plant.

Corn only has to be weeded in the early stages. Once the corn is around a foot tall, you don’t need to weed it.

Harvesting Corn

You want to wait until the ears get fully developed and are plump. The silks start to turn brown and begin to dry up. It is important to harvest the corn shortly after it matures, as it will start to turn to starch and lose it’s sweetness.

Traditional Three Sister Plantings

I have been asked about doing the traditional corn, bean and squash planting. Some have stated that it didn’t work or they had problems.  A few tips to keep in mind is that you should use popcorn, field corn that will be used for flour or meal or animal feed, or ornamental corn. This means that the corn will have to be fully mature and dry before harvesting.

Happy planting, and enjoy a real treat, sweet corn!