Have You Ever Wanted To Know How To Grow Sweet Corn?
I learned how to grow sweet corn as a young lad working in my family’s home garden under the tutelage of my lemonade sipping dad. He sat there, in his wide brimmed straw hat – under a big ole shade tree – with an ice cold drink – making sure kept the garden tilled and free of weeds. Boy, he was a hard worker!
I mean – who doesn’t like sweet corn. Considering that over 70% of the foods and beverages we consume contain corn in one form or another: syrup, oil, corn starch, corn flour, corn mash, popcorn, candy corn – the list is seemingly endless. Even our livestock eats corn – both the ears and the plants themselves (fodder). I would think everyone would want to pick up on these easy steps for how to grow sweet corn, don’t you?
It is used to make ethanol, an additive in gasoline that fuels our cars. There are specially made “corn-burning stoves” for home heating. Corn starch can be found in plastics, batteries, cosmetics, deodorants, denatured alcohol, cough drops, hard candies, baby diapers, matches, medications, carpet, crayons, glues, toothpaste, dish detergent, paper, clothing dyes, explosives, soaps…
Suffice it to say that without corn, our world would literally fall apart!
But, most of the corn produced is GMO (Genetically Modified Organism).
To discourage the pests from destroying the crops.
In Europe, there is a requirement to list products containing GMO ingredients on the food package label.
But, the good ole’ USA doesn’t have this constraint. In 2016, the President signed a GMO bill that only requires companies to add QR codes or 1-800 numbers to the label. Then, customers have to take additional steps to find out about GMO components in the foods they buy.
Corn is so very easy to grow so, why not grow our own non-GMO variety for consumption?
Let’s Plant Some Sweet Corn.
Sweet corn varieties* are available as Yellow, White, Bi-Color, and Multi-Color…and include:
- Standard Sweet (su) – Contains more sugar and less starch than field corn. Field corn is grown to feed farm animals.
- Sugary Extender (se) – Contains higher sugar content than Standard Sweet (su).
- Supersweet (sh2) – Contains 4 to 10 times the sugar content of Standard Sweet (su).
- Synergistic (sy) – The ears of this variety contain a combination of Supersweet, Sugary Extender, and Standard Sweet kernels on the cob. Also, they don’t have to be isolated from other varieties…even though isolation is still best for maximum sweetness.
- Augmented Supersweet – Supersweet, Sugary Extender, and Standard Sweet characteristics in all kernels, which are very tender.
* Wikileaks has an extended list of sweet corn varieties.
Ensure that you buy “non-GMO” seeds. We are trying to get away from GMO products as much as possible, aren’t we?
What Sweet Corn Do I Like?
Well, I have several sweet corn varieties that my mouth waters for…
Corn is a ravenously hungry plant! If you performed a soil test and fertilized your garden area based on the test result recommendations, you won’t need to add fertilizer before planting corn. If you haven’t fertilized your garden, add a cup of 10-10-10 fertilizer per 15 to 20 feet of row and rake it into the loose dirt.
In 6 to 8 weeks, when the corn develops its tassels, fertilize the plants again. If you see the dark green corn leaves start to turn lighter green then, the corn plants are hungry. Give them another dose of fertilizer.
Plant only ONE variety of corn per section in your garden and keep the sections as far away from each other as possible especially, if their sweetness levels are different. Cross pollination between varieties can lead to increased starchiness and decreased sweetness in your ears of corn.
How to Grow Sweet Corn?
Prepare and Plant the Seeds
Using the same method I use for my green beans, I don’t use the germination station for corn seeds. I soak the seeds overnight to give them a better chance to germinate then, I plant them directly into the soil. Drop several seeds into a hole about an inch deep, cover with a little potting soil, mixed with dirt, space the seed holes 8 to 12 inches apart in the row, and space the rows no more than 24 to 30 inches apart. This will help the plants pollinate with each other when it becomes time.
Since I usually keep the rows in my garden 4 to 5 feet apart, the 24 to 30 inch row spacing for corn works great!
Firm the dirt covering the seeds with your hand for better soil-to-seed contact. This helps the seed germination process.
Corn likes to be in an area that gets full sun at least 6 hours a day.
Water well and label the plants. Then, if the corn is to your liking, you will know what type of seeds you want to plant next year.
When the plant grows to about a foot or two high, bank some soil up the sides of the stalk at least 6 inches…creating a hill around it. This technique will give support to the plant and help straighten it back up in a few days if high winds push the plant over. At this point, consider using The Three Sisters method of companion planting which adds sister green (pole) beans and sister squash to sister corn.
A Unique Pollination Process
Shortly after the tassels form at the top of the stalk, they will open up and show loose, yellow pollen hanging from them.
The ears will start to show white silk coming out of their ends. Yellow pollen has to get to the white silk to pollinate the ears. The silk carries the pollen down to each kernel (ovule) and impregnates the kernel.
The silk turns brown or reddish-brown and the kernel becomes juicy and sweet.
Help the Corn! Hand-Pollinate!
In large fields of corn, the wind is normally strong enough to agitate the stalks back and forth helping the pollen fall on the plant and reach the ear silk. But, in a backyard home garden, sometimes the wind doesn’t do its job efficiently.
So, to improve your harvest, hand-pollinate your plants by either snap off an opened up tassel from one or two of the plants and walk down the rows of corn “feather dusting” the ear silk…or, reach up to shake a tassel on each plant so that loose pollen drops down onto the silk…to ensure pollination takes place.
When the ear silk turns brown or reddish-brown, at least on the ends, the ear is pollinated! Perform this hand-pollination technique for several days, in the morning, after the dew dries, or, in the early evening…and I guarantee it will increase your yield significantly!
Good News / Bad News
The Good News is…eating corn from your own backyard garden is as close to heaven as you will get on this earth.
The Bad News is…each stalk will only produce ONE ear…maybe TWO, if you’re lucky. Planting late-maturing corn offers a higher probability that the plant will produce two ears. But, either way…it makes me feel kinda cheated after caring for these plants so diligently. So, if you want to eat some ears throughout the growing season, stagger plantings every couple of weeks.
Pests and Diseases
There are a number of pests that love corn, including aphids, beetles, borers, and birds (remember the Scarecrow in the Wizard of Oz)…but, the corn earworm is the biggest nemesis of the beautiful sweet ears we grow!
The adult Corn Earworm Moth flies around at night dropping eggs on ear silk. The eggs hatch and the earworms (larvae) crawl under the husk to joyfully find a bountiful supply of food. As the earworms grow bigger, they will feast on each other but, there will always be one of them left to nibble on the sweet kernels.
Kill the Earworm!
Mineral oil will kill the earworm! Open up the husk enough to see the very end of the ear and put a half dozen drops of mineral oil on the tip. The oil will run down inside the husk…coat the ear…and, smother the earworm. Dead as a door nail!
Do NOT apply mineral oil to the corn ear until AFTER you are absolutely certain that the ear has been pollinated! The mineral oil will prevent the ear from pollinating properly…and, all your loving efforts to grow sweet, tasty corn will be “all for naught.”
Plants that will repel earworms: cosmos, geraniums, and thyme.
A number of diseases will infect crops. Among them is Corn Leaf Blight. But, I have found most of these diseases to be insignificant and not worthy of my attention.
When to Pick?
When the ears are growing, they are pointed at the ends. As they ripen and mature, the ends become rounded or blunted. Also, the brown or reddish-brown silk gets very dry since it has detached from the kernels. If the ear shows all these indications, then grab hold of it, pull downward in a twisting motion, and snap it off the plant.
If you have doubts that the visual clues of ripeness aren’t enough, gently peel back part of the husk and look at the kernels. Seeing is believing! Are most of the kernels soft and juicy-looking? Then, pick it!
I will normally remove the husks while in the garden and check the ears for earworms. If I find these little critters, I cut off the section of the ear containing them and the rest of the ear is fine for my dinner table.
And, if there are no more ears growing on the stalk, I pull the stalk up by the roots and remove it from the garden area…along with any husks or earworm-infected pieces of corn.
So, there you have it. How to grow a corn plant successfully!
Next, I always head for the kitchen and hope there is already a boiling pot of water ready for our corn-on-the-cob dinner!
Talk to Your Plants
Now, I don’t know about you…but, I’m a firm believer in talking to the vegetables in my garden…with the exception of the corn plants. They never listen to me! Everything I say to them goes in one ear…and out the other.
My neighbors say that, being a lifetime gardener has made me way…way…too corny. But, I disagree. What do you think?
Do you have some thoughts or a story about growing corn…or, how corny I have become? Let me know in the comments below or email me: firstname.lastname@example.org.
Jim, the Life Long Gardener