There is nothing like an ear of your homegrown fresh corn roasted on the grill. The effort it takes to grow this crop is well worth the results. The versatility of corn—from sweet corn ripened and eaten off the cob to dried kernels that are ground and used for meal—make this vegetable a must-have for any home gardener.
Because corn is primarily a wind-pollinated plant and a heavy feeder, careful site preparation is necessary. You’ll want to grow your corn in short blocks rather than in one long straight row. Each grain of pollen shed from the tassels of the plant must migrate to the silk strands emerging from the developing ears and growing in blocks will ensure this is managed. For instance, in a 5 x 5 block, twenty-five plants can be grown, spaced one foot apart. This is a good way to start growing corn on a small scale and get your feet wet if you’ve never grown corn before.
Corn needs well-drained soil with a pH range of 6.0 to 6.8 and a site that is in full sun. It’s best to begin your spring planting preparations the preceding fall by planting a green manure crop and leaving it in place throughout the winter. Till it into the soil about two weeks before you intend to sow your seeds.
Spread about 2 inches of compost over the planting area and water that down with a fish emulsion fertilizer such as Protogrow®. Turn this mixture into the dirt, digging it in several inches. Your corn’s color will tell you if additional fertilization is necessary. Healthy plants have dark green leaves. If your plants are in need of nourishment, their color will turn light green. If this happens, feed them again.
When to Plant
Sow your seed after all danger of frost is past. In the South and other long-season areas, you can do succession plantings every two weeks until three months before the first fall frost date.
How to Plant
The usual depth for corn seed is one inch, but in cool soil you’ll need to sow a little more shallowly, while in hot soil you’ll need to sow a little more deeply. You’ll need to water your furrows well and then plant your seed. Firm them in place and cover, then water in again. Sow your seeds 3 to 4 inches apart in rows three feet apart. Thin your seedlings to 10 inches apart (up to 2 feet apart for tall varieties).
You can sow your seeds 3 to 4 inches apart in double rows 1 foot apart. Allow 3 feet between the double rows and thin your seedlings to 12 inches apart. If utilizing this method, do not choose a tall variety of corn.
The ideal germination temperature for your seed is 70 degrees F to 85 degrees F. Plant growth will come to a halt if adequate water is not provided. Corn grows quickly and has shallow roots, so it needs plenty of consistent watering. Keep a check on the soil and when the top two inches of dirt has dried out, water again. Make sure when you water the dirt is wet about six inches down. Mulching with organic mulch will help the soil retain moisture as well.
If you don’t have a drip irrigation system set up in your garden, you can dig shallow irrigation trenches between your rows and water these areas when your corn needs watering. This will allow the water to soak into the surrounding area without destabilizing your corn stalks and it won’t soak the foliage down, which can encourage disease and pest infestation.
When the stalks are about 12 inches tall, you’ll need to begin to hill up additional soil at the base. This will stabilize your corn against any inclement weather or wind.
You also want to leave any suckers (small side shoots) on the plant. They don’t harm anything and they don’t reduce yields, but removing them can damage the stalk and leave the plant open to disease and pest infestation.
If you are planting more than one variety of corn, you’ll want to avoid cross-pollination. You’ll need to isolate the different varieties from each other with a distance of at least 400 yards. You’ll also want to make sure to plant your varieties a month apart from each other so that maturity (and pollination) dates are not all the same.
Depending on the type of corn you plant, harvest times can be anywhere from 60 days to 100 days. It’s a little difficult to know when the optimal harvest time comes around, but generally, when the silks are brown and dry, with just a little fresh green at the base, your corn is nearing harvest. Squeeze the husk and feel if the kernels feel full and ripe. If so, peel just enough of the husk back to expose a small portion of the ear and poke a kernel with your fingernail. If a milky liquid leaks out, the corn is ripe and ready to pick. Once the silks begin turning brown, check your corn daily. Usually the corn planted in one sowing comes in at the same time.
You’ll want to harvest your ears in the morning, when it’s still cool. Grab the ear and twist it down, away from the stalk. It’s best to eat your corn as soon as possible after picking since the sugars in corn turn quickly to starch once it’s harvested. If you don’t intend to eat your corn immediately, then blanching and freezing as quickly as possible will preserve the sweetness of your garden fresh corn.
There are a number of diseases and pests that attack corn plants. Skeletonized leaves can be caused from Japanese adult beetles, which also attack the silks. The larvae of these beetles feed on the roots of the corn and can destroy the plant that way. There are also corn earworms, southwestern corn borers, corn seed maggots, flea beetles, corn rootworms, and corn sap beetles. Check with your county extension agent for the best remedies for your area.