Row by Row Episode 190: Everything You Need To Know About Growing Sweet Corn
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One of the most popular vegetables in the United States is corn, especially sweet corn. Scientists believe people living in central Mexico developed corn at least 7,000 years ago. It started from a wild grass known as teosinte. Tonight we discuss when to plant, where to plant, water requirements, and much more.
General Information
- Sweet corn is a warm-season crop and must be planted after the soil warms and there is no more danger of frost; at least above 55 degrees F. (13 C.). If you plant super sweet corn, be sure the soil is at least 65 degrees F. (18 C.), as super sweet corn prefers a warmer climate.
- Plant the corn seeds about 1 inch deep and 3 to 4 inches apart in the row. Space the rows 2½ to 3 feet apart. After the plants are up, thin them to 1 foot apart. If you plant them closer, your corn will have small, poorly-filled ears.
- Plant in full sun
Part 2
- Sweet corn must self-pollinate or pollinate by a similar variety. Wind moves corn pollen from the tassel at the top of the plant to the silks of the ears, and to lower parts of the plant.
- Always plant corn in blocks of at least four rows. Corn planted in a single row will have much of its pollen blown out of the row, and will produce ears that have blank areas where kernels did not form.
- If you garden in an agricultural area, try to plant your sweet corn 300 feet from the nearest cornfield. Large acreages of field corn will produce so much pollen that you could spoil your crop unless you plant your sweet corn far enough away.
- Different varieties produce pollen at different times, so you can isolate them by time. Since different varieties will respond individually to growing conditions, do not isolate them with less than two weeks until the given “days to maturity” in the variety description.
- You can also plant one variety earlier than another variety to achieve the needed difference in pollen production.
Water Requirements
- Water sweet corn as needed to keep it from wilting. Do not let corn suffer from lack of water when the kernels are forming.
- One inch of rainfall per week is good for your corn.
- Drip Irrigation is best to use with corn
Pests and Diseases
- Two insect pests that feed on the developing ears of corn are corn earworm and European corn borer.
- Smut causes firm, tumor-like growths on leaves, stems, ears and tassels. Look for smut galls throughout the season and cut them out before they produce spores. Remove these galls from the garden and bury them. Do not compost them.
- Leaf rust appears as rusty orange streaks on leaves that release an abundance of powdery orange spores. Rust resistant varieties are available and are the best form of control.
- Use good cultural control practices to reduce disease problems to a good level and allow for a successful harvest.
Harvesting
Corn is ready for harvest about 3 weeks after the tassel grows on top of the corn plant. Corn is ripe when juice from the kernels is milky white, the silk on the ears has turned dark brown. The best time to pick corn is in the early morning or evening when it is cool. Place it uncovered in the refrigerator for 1 or 2 days. Corn stored for more than 2 days loses its sweetness.