When it comes to growing crops, corn is among the most specific when it comes to planting conditions and harvesting. Knowing when to harvest corn involves monitoring the growth of your corn stalks to ensure you harvest when the ears of corn are at their peak.
Different types of corn are grown worldwide for various purposes, and each of them is unique in how they grow and how we harvest them. Sweet corn is the type of corn grown, harvested, and manufactured for human consumption. Harvest this corn 60 to 100 days after planting; however, there are essential visual cues that tell gardeners when to harvest their corn.
This type of corn differs from field corn, which gardeners use as livestock food. The difference in the usage of these corn types is also evident in how we harvest them. Continue reading to find answers to common questions like, “How long does it take for corn to grow?”
When to Pick Corn (Maize)
It depends on the use when harvesting corn and the question of “How long does it take for corn to grow?” The corn we consume is sweet with chewable kernels because we pick them while the stalks are immature. Other types of corn, especially field corn, are not edible for humans because of how long they remain on the stalk.
What is Sweet Corn?
Humans love sweet corn for its high sugar content. The sugars inside the corn kernels form due to a conversion of the natural starch in corn into sugar. To produce the sweet taste and chewable texture we love, farmers who mass produce corn harvest it before it reaches maturity. This stage in the corn stalk’s growing cycle is called the milk stage.
The usage of sweet corn dates back to the 1700s when Native Americans introduced sweet corn to the Europeans. From there, the popularity of sweet corn spread and eventually led to the creation of cultivars with higher sugar content.
Normal sugary corn (su) has the lowest sugar content of the cultivars. Normal sugary corn has a fast conversion fate of sugars turning to starch and a short harvest window before the kernels lose their flavor.
Sugary-enhanced corn (se) has around 17% sugar content and more stable sugar levels than normal sweet corn. The higher sugar content in this type of corn gives it a longer harvest window thanks to the medium rate it takes for its sugar to turn to starch.
The sweetest type of corn, also known as supersweet corn, is Shrunken-2 (sh2). This corn has the highest sugar content and cannot convert its sugar to starch.
When to Harvest Corn
Deciding when to pick corn is one of the most significant factors in the quality of the corn you harvest. Corn harvest time depends on the type of corn seed planted. The fastest corn to reach maturity is normal sugary corn that matures in 58 days. Blue Hopi, a Shrunken-2 corn, reaches maturity in around 110 days.
Because there is such a big gap in how long it takes for corn to mature, the best way to determine when corn is ready is to monitor the corn silk. As corn ears develop, silk threads emerge from the top of the shoot.
These silk threads are the stigmas of the female flowers of the corn plant. Each thread connects back to an ovule inside the shoot. Once pollen from the corn tassel, or the male flower that blooms at the top of the corn plant, reaches the threads, it fertilizes the ovule and allows it to develop into a kernel.
Because of the tassel placement above the threads, pollination happens easily, usually due to the wind; however, many gardeners and farmers shake the corn stalks daily to ensure pollination.
When are corn ready to pick? Your corn is ready for harvest about 20 days after the appearance of the corn silk. One way of knowing when to pick corn is by testing the kernels with your fingernail. The ears are ripe for harvest if the kernels produce a milky liquid.
How to Harvest Corn
The best time to take care of harvesting corn is in the early morning after the morning dew has dried on the corn plants. To pull corn from its stalk, grasp the ear and pull down, twist the ear and pull again.
Because corn stalks typically grow at least two ears, only harvest what you plan on using within the week and return to harvest the rest while it remains in the milk stage—waiting too long results in harvest loss due to the kernels losing their flavor and texture.
Once you harvest all the corn on the stalk, pull the stalk from your garden and add it to your compost pile. Farmers in the corn belt of the United States with corn fields may use the stalk for corn silage depending on the stalk quality.
When sweet corn is ready for harvest, the goal is to maintain the flavor of the corn. To accomplish this, harvest the corn whole on the cob. When we harvest fresh corn, the husk is left on to protect the kernels until it’s time to shuck the ears and cook the corn.
What is Field Corn?
Field corn is any corn used to produce animal feed, processed foods, or grain alcohol. There are various types of field corn, and the most popular are dent, flour, and Indian corn. Field corn is sometimes called cow corn because cattle are the main animals that farmers use field corn to feed.
As the name suggests, we grow flour corn to produce corn flour. Flour corn grows starchy kennels filled with starchy tissue. To make corn flour, we use the entire kernel, whereas only the starchy interior gets used to make cornstarch.
Dent corn has dented kernels at the time of harvest. This corn goes through various manufacturing processes before companies make it into food items.
Indian corn is known for its multi-colored corn cobs; however, we don’t typically eat it. It is more common to see Indian corn as an ornamental decoration around the holidays.
How to Harvest Corn for Animal Feed and Processing
The most significant difference between harvesting sweet corn and field corn is that we harvest sweet corn while it is still immature. Waiting too long to harvest sweet corn results in a yield loss as the kernels become starchy and practically inedible due to moisture loss.
Plant moisture is the biggest reason for the delayed harvest timing when harvesting field corn. Harvest field corn later in the growing season to allow the ears to dry out and lose most of their moisture.
As corn stalks lose their moisture, the leaves surrounding the corn crop turn from green to brown, and over time, the stalk itself turns brown. Farmers harvest dry corn so that the corn has little moisture to hold up to mechanical processing.
Field corn is ready to harvest once the silks turn dark brown and the stalk begins to turn brown as it dies. The corn stalk no longer supports the weight of the corn, and the ear may end up pointing at the ground as the stalk sags.
The corn farmers harvest for their livestock is sometimes called wet corn. Wet corn is corn harvested with at least 24% grain moisture content. This corn is stored in a silo to ferment before being eaten as animal feed.
Corn is a warm-season crop; growing it involves germinating your seeds at least 60°F because corn thrives in warm weather. It is not hardy to cold temperatures but recovers when temperatures drop below 30°F.
Depending on your part of the country, cold weather may not be a concern. For home gardeners living in the northern areas of the United States, one option for avoiding frost is to plant corn indoors.
Although corn does not transplant well, one solution is to start growing corn in a biodegradable pot. Growing corn in containers that break down over time allows you to plant your corn plant, in its original container, in the garden for it to degrade in the soil.
When seeding outdoors or transplanting, if you plan on growing different varieties, the best method for planting corn is to group them by type. Cross-pollination for corn is expected, creating poor results, so separate your corn cultivars by at least 300 yards. Stagger planting by two weeks to draw out your growing season.
Planting Corn Seeds
When planting corn in a small garden or a large plot, plant corn in blocks based on type. Sow sweetcorn seeds separately from non-sweet varieties to avoid growing an ear of corn with starchy and inedible kernels.
Prepare your garden for corn seeds by monitoring the soil temperature and removing weeds in the area. Combine compost with the top two soil layers and sow corn seeds three inches apart. Thoroughly water your seeds and wait for them to germinate.
When you planted corn seeds and once your corn seedlings sprout, thin them to leave one seed for every foot of space. Because corn roots are susceptible to stress, avoid pulling seedlings out of the ground and use shears for thinning.
It’s essential to weed your garden before your seeds sprout to avoid disturbing your corn stalk’s roots. After your corn plants begin growing, add organic matter mulch to the garden to cover any weeds and prevent them from growing.
Corn plants do not handle nutrient competition well, and mulching is the perfect way to avoid causing stress to your plants while keeping weeds at bay.
Regularly water your corn stalks as they grow, especially once the tassels form. Corn stalks need at least one inch of water per week. Less watering causes stress to your plant, resulting in corn cobs with missing kernels.
While your corn plants grow and develop their ears, monitor your corn stalks for signs of pest damage. The European corn borer is one of the common problems growing corn that likes to attack corn stalks. To kill corn borers and worms on your plants, apply a drop of mineral oil to the top of the ear to smother any insects inside.
Using Corn After Harvest
After harvesting corn, you might think your only option for enjoying your corn is to eat it off the cob; however, removing kernels from the cob is easy. Once your corn is indoors, remove the husks from your corn by removing a few leaves at a time until the cob is bare.
Break off the husk at the base of the corn ear and rub the corn in one direction with your hands to remove the silk threads between kernels.
To remove kernels from the cob without making a mess, place a small bowl upside down inside a larger bowl. Press the edge of the cob against the bottom of the small bowl and use a sharp knife to slice kernels off the cob.
Carefully cut downward, as close to the base as possible, without cutting into the cob itself. Continue cutting until all sides of the corn are clear of kernels. If you aren’t ready to cook with your kernels, place them in a freezer bag to store sweet corn for a long time in the freezer. Cook your kernels in a steamer or in boiling water.
Preheat the oven to 375°F and spray a baking dish with nonstick spray. Mix your cream cheese, butter, and garlic in a pan over medium heat. Add the milk and mix until smooth. Mix in your corn kernels and continue stirring.
Add thyme and season with salt and pepper to taste. Spread the corn mixture into the dish and top with shredded cheese—bake for 15 minutes before serving.
When you harvest corn depends chiefly on the type of corn you grow. Unless you’re looking to feed livestock, the best time to harvest your corn is while your sweet corn is still immature and in its milk stage.
We hope you learned when to harvest corn from our guide and will share our tips on how to harvest corn plants with your friends on Facebook and Pinterest who are interested in learning about corn crops.