There is one way to enjoy fresh sweet corn properly, and that is on the cob. Some people enjoy just standing out in the garden and eating it raw. But for the ultimate experience, try grilling the cobs and serving them with butter and pepper.
- Full sun.
- Ample moisture.
- Soil pH around 6.0 to 6.8.
- Cowpea. Studies suggest that this combination may increase the yields of both plants.
- Pigweed. May pull nutrients up from the soil, giving corn roots easier access.
- Sunflower. Repels pests and attracts beneficial insects.
Despite popular advice, letting pole beans climb the stalks does not benefit the corn, and may result in cobs becoming strangled. Likewise, squash will compete with the corn for water.
- Feed the soil well the fall before planting. Use plenty of compost.
- Plant outdoors when the last spring frost is past and the soil has warmed above 70°. In Kansas, late April is the earliest safe time. Depending on the variety of corn you are planting, you may be able to plant as late as mid-June.
- Soak the seeds for a couple of hours before planting.
- Plant one or two inches deep and 12 to 18 inches apart. For best pollination, plant corn in squares or blocks, not rows.
- Water the soil and keep it moist until germination.
- For a continuous harvest, plant a new variety with a different maturation date every couple of weeks until the safe planting dates are past.
The major requirement of corn is water. Be generous with the water on those hot, dry, windy days. A hay mulch will help you keep up with it.
Pests and Diseases
- Corn borer.
- Corn earworm.
- Common rust.
- Northern corn leaf blight.
- Stewart’s wilt.
As the ears of corn grow, keep an eye on them, especially after the silks turn brown. Run your hand over the ears periodically to see if you can detect full-size kernels. If you can, gently pull back a small piece of the husk to inspect the cob. Poke your thumbnail into one of the kernels. If the juice is white and milky instead of clear and watery, the corn is ready for harvest.
To harvest sweet corn, grab the stalk with one hand and an ear with the other. Bend the ear sharply to the ground to break it away from the plant.
After you have harvested all of the corn, it’s best to cut down the stalks to avoid attracting insect pests. Chop them up and put them in the compost pile.
Homegrown corn is best when eaten at its freshest. If you must store it for a few days, husk and refrigerate.
To store corn for an extended period of time, blanch it, cob and all, as soon as possible. This will take about four minutes. Once the corn is blanched, cut the kernels off of the cob and either freeze or dry.
- Isolate corn varieties by one to two miles. If this is not possible, be prepared to bag tassels and ears.
- Raise at least 200 corn plants to avoid inbreeding—corn is highly susceptible to the negative effects of inbreeding.
- Whenever you see husk leaves appearing on the stalk, cut off just enough of the husk to reveal the silks, still leaving some husk to protect the cob.
- Cover the ear with a bag.
- Bag tassels when anthers, dangling yellowish structures that produce pollen, begin to appear along the tips of the branches. Use staples to keep the bag shut.
- In late morning or early afternoon the next day, gently bend the tassel over and shake the pollen into the bag.
- Combine the pollen from all of the tassels you bagged to avoid inbreeding.
- Trim the silks on each of the ears you bagged to about one inch.
- Shake half a teaspoon or so of pollen onto the silks of each ear.
- Cover the ears again with the bags from the tassels.
- Allow the ears to mature and fully dry on the stalks.
- Harvest the corn and remove the husks.
- Let the cobs dry thoroughly in a sheltered location.
- When the kernels are completely dry, rub them off with your hands or by rubbing two cobs together. If you have a corn sheller, this can make the task easier.
- Winnow in front of a fan.
- Mix the seeds from the different plants to avoid inbreeding in the future.
- Store seeds in a cool, dry, dark place. They should keep for up to three years in ideal conditions, but be aware that corn seeds are very finicky. It doesn’t take much to make them spoil.
Sweet Corn Factsheets
Information on a wide range of corn diseases.