How to grow Corn?

- Latin Family: Poaceae
- Latin Genus: Zea
- Ease of Growing: Easy
- Growing Type: Annual
This warm weather annual differs from all other common garden vegetables in being the only member of the grass family (Poaceae). Corn has a very distinct personality and after growing it for a while you can understand why Native Americans considered it much more than just a plant. Kids love to grow corn because it's easy, beautiful and tastes so good.
Corn History
Corn is thought to have originated somewhere in Central America, though it is no longer found there as a wild plant (it may be descended from the closely related Teosinte, which is still found in the wild in Mexico). Native Americans have cultivated corn for over 5000 years and in many places it was not only a staple food, but also an integral part of their culture. Corn was introduced into Europe in the sixteenth century and spread from there to all suitable climates around the world.
Soil Preference
- PH (min/max): 5.5 - 7.0
- PH Ideal (min/max): 6.0 - 6.8
Corn will grow well in a variety of soils, but it is a hungry plant and needs a lot of nutrients for maximum production. The ideal soil is rich, moisture retentive and well drained.
How to care for Corn?
Corn is fairly easy to grow if it has warm conditions and enough nutrients, light and water. You then just have to make sure it gets pollinated properly. You need to be growing enough corn plants in a block to ensure good pollination, a minimum block of 4 feet.
Water
The best way to irrigate is with a soaker hose or a drip system. Don't use sprinklers during the pollen shedding stage, as it may affect pollination.
Fertilizer
Corn is a notoriously hungry plant, which isn't surprising when you consider how fast it can grow. For best growth it needs generous amounts of nitrogen, phosphorus and potassium, as well as all of the other plant nutrients.
Seeds
Seed Viability: 1 - 3 Years
Germination Percentage: 75.0
Saving Seed: Corn is wind pollinated. Separate varieties by 600' for home use, or 1/2 to 1 mile for absolute purity. Save at least 500 seeds from at least 10% of the plants to maintain vigor and genetic diversity of the variety.
Saving corn seed is a little more complicated than most other crops, because you have to worry about inbreeding (Corn strains are very inbred). It is said that if you want to maintain a pure variety indefinitely you need to save seed from at least 50 plants (some say a minimum of 100), to keep sufficient genetic variability.
Hand pollination: This isn't difficult, but takes some time, especially if you are pollinating 100 plants. The first step is to put a bag over the female flowers before the silks emerge, to prevent them being pollinated by any stray pollen. This must be taped shut, to prevent any pollen entering. The next morning, after the dew has dried, you go out and gently shake pollen from the newly opened tassels into a paper bag. Then simply transfer a little pollen onto the silks of each plant with a brush. You then replace the bags and leave them on until the silks go brown. Mark the ears carefully so they don't get eaten accidentally.
Light
Sun: min. 6 hours daily
Corn uses an especially efficient form of photosynthesis that enables it to grow rapidly in the high intensity light and heat of the tropics. It should be placed in the sunniest spot in the garden.
Conditions:Warm, Hot
Season:Short Season, Long Season
Storage
Old fashioned open pollinated sweet corn starts to deteriorate as soon as it is picked, hence the (somewhat tongue in cheek) advice to have the water boiling before going out to pick. The best way to store sweet corn is to remove it from the husk and freeze it in plastic bags.
Storage Req: Freezer
Storage Temp: 32°F
Storage Length: 1-360 days
The newer super sweet hybrids stay sweet much longer and can be kept in the fridge for several days.
Ears of corn in their husks can be kept in the refrigerator for a couple days. The sooner you eat them, the better.
Storage Req: Refrigerator
Storage Temp: 35-40°F
Storage Length: 1-5 days
Field corn or flower corn used for making corn meal and other corn products. The dry ears can be stored whole (they are quite decorative), but the seed takes up less space if you remove it from the ears. Make absolutely sure the seed is completely dry before storing it, otherwise it will go moldy.
Storage Req: Dry
Storage Temp: 60-70°F
Storage Length: 1-360 days
Problems
Suckers
Corn plants often produce suckers, smaller stems,which if left alone may eventually flower and produce small ears. Some people believe theses drain energy from the plant and remove them as they appear. This isn’t really necessary though.
Corn Earworm and Corn Borers
Corn earworm can be suffocated by inserting a medicine dropper half filled with mineral oil into the silk after it has wilted and browned at the tip (4 to 5 days after silk appears). Corn borers can be prevented by composting corn refuse and stubble as soon as possible.
Corn Smut
Corn smut forms large puffy, gray, irregular masses of fungus during dry hot weather. Corn smut is a delicacy in Mexico, but if you want corn rather than corn smut, remove and destroy the fungus; otherwise the black spores will re-infest your corn for several years.
Corn Types
- SuperSweet / Hybrid (sh-2)
- Ornamental
- Organic / Hybrid
- Open Pollinated & Heirloom
- Flour Corn / Field Corn / Ornamental
- Popcorn
- Sugary Enhanced / Hybrid (SE)
- Standard / Hybrid (su-1)
These varities contain a shrunken gene that makes them very sweet. However they need to be isolated from other varieties while tasseling, or the resulting kernels will be tough and starchy.
These plants are grown specifically for decorating purposes. There are many types of ornamental corn, with a wide range of different sizes, colors, and husks.
Corn is one of the few crops in which hybridization has made a big difference. Hybrids are superior to non-hybrids in that they mature more uniformly and are often sweeter. Unfortunately, you can't save the seed of a hybrid, as they don't come true to the type. While these varieties of corn hybridized seed, they are also organic.
There are relatively few open pollinated heirloom sweet corn varieties still available and they have pretty much disappeared from commercial growing because the newer hybrids stay sweet for much longer. However, some cooks maintain that sweetness isn't the only thing that makes for a great sweet corn and that the old open pollinated heirloom varieties have a superior flavor. If you grow them you just have to be more aware of their ripening, as they ripen all at once and don't maintain their sweetness for very long.
Corn flour is synonymous with cornmeal. Flour corn is made almost entirely of soft starch. The kernels are soft, mealy, and easy to grind. Within this type we also include 3 sub-types of Field Corn: Dent (including Gourdseed), Flint, and Soft.
Dent (Z. mays var. indentata): The kernels of this corn have a depression in the middle and their starch is a mixture of hard and soft. Almost 80% commercial corn is this type. Depending on when they are picked they can be used for cornmeal, hominy, roasting corn or sweet corn.
Gourdseed is an old type of dent corn once widely used for cornmeal and considered superior for cornbread. Gourdseed corns are some of our oldest corns, and were commonly grown in southern Virginia. The plants of gourdseed corn are heavily stalked and bear ears having a large number of rows of thin, deep kernels. These valuable corns originated from Indian gourdseed corn dating back to at least 1700. They were used for roasting ears, and for feed and flour.
Flint (Z. mays var. indurata): The very hard starch in the semi-translucent seeds earns this the name Flint corn. It grows well in cooler climates than other corns. It is used for cornmeal, though it is so hard it can be difficult to grind.
Soft (Z. mays var. amylacea): The seeds contain mostly soft starch. This type of corn is easily ground into meal and is commonly used for bread, tortillas, and corn chips.
Flour corn varieties can also be showy, which makes them good for decorating purposes, too. There are many types of corn that can be dried and displayed, with a wide range of different sizes, colors, and husks.
Pop Corn kernels have a very hard outer layer and a soft inner layer, a combination which makes them pop very well. They can also be used for cornmeal. Popcorn is a great crop for children to plant, as they get an extra special reward at the end of it.
Sugar enhanced corn varieties contain the sugary enhancer gene (su), and makes the kernels sweeter and more tender. In addition, the sugar is only slowly converted to starch after picking, so they remain sweet for longer. They do have a thinner kernel skin, and need to be handled a bit more carefully, but that also makes them more tender. These varieties don't need to be isolated from other varieties.
Corn is one of the few crops in which hybridization has made a big difference. Hybrids are superior to non-hybrids in that they mature more uniformly and are often sweeter. Unfortunately, you can't save the seed of a hybrid, as they don't come true to the type. This type is sometimes referred to as Normal Sugary or (su), to differentiate it from other types now available.
Pests
- Corn Rootworm
- Wireworm
- June Beetle
- Caterpillars
- Flea Beetle
- Birds
- Blister Beetle
- Corn Earworm
- Stink Bug
- Leafhoppers
- Aphids
- Carrot Beetle
- Cutworms
- European Corn Borer
- Japanese Beetle
- Crickets and Grasshoppers
- Leafminers
- Rabbits
- Raccoons
- Rats and Mice
- Gophers
- Deer
Diseases
- Anthracnose
- Bacterial Wilt
- Corn Smut
- Rust
- Dwarf Mosaic Virus
- Corn Leaf Blight
- Damping Off
- Late Blight