Florida's sweet on corn

Starting in January and often ending in April, Central Florida sweet corn farmers are planting their seeds — roughly one inch deep, six to eight inches apart with approximately 30 inches between rows.

Two to three months later, it's time to harvest — most of it by hand. Garrison, Legion, Passion, Obsession and Supersweet, to name a few varieties, are ready to be picked.

Corn grows well in many places in the world. In fact, it grows on every continent except Antarctica. What corn needs most is fertile, well-drained, moist soil.

Corn is often planted after short season crops, such as sugar cane, green beans and rice.

The United States is the largest producer of corn in the world. It's also typically ranked as one of Florida's most valuable vegetable crops. Others include tomatoes, snap beans, bell peppers and cucumbers.

According to UF Extension, "Florida ranks No. 1 nationally in the production and value of fresh market sweet corn, typically accounting for approximately 20 percent of both national sweet corn production and of U.S. cash receipts for fresh sales."

Furthermore, 589 million pounds of fresh sweet corn, valued at $189 million, was produced on 42,100 acres in Florida during the 2009-10 season (Sources: USDA and the Florida Sweet Corn Crop profile, 2011).

The Everglades area — Belle Glade, South Bay and Pahokee — has more than half of the state's sweet corn production, while Miami-Dade, Hendry and Collier counties have about a quarter.

Although sweet corn seems like the perfect crop to grow, as with any crop it has its challenges, such as insects, diseases and weather conditions.

"Insects are a big challenge, especially worms, and a relatively new pest: the corn silk fly," said Gene McAvoy, Hendry County extension director.

He explained that the fly feeds on the silk, while the larvae disrupt pollination and reduce kernel density.

"There are about 42 different insects of concern for corn growers, such as the corn earworm, the lesser cornstalk borer, aphids, wireworms and cucumber beetles — many of which can literally eat the crop to the ground or render it unmarketable," said McAvoy.

Insecticides are applied via airplanes and tractor-drawn ground sprayers.

"The fall armyworm that favors drought conditions is a worm we often have to contend with," said Pablo Sanchez, who has 1,500 acres in Hendry County, 500 of which are used to grow several varieties of white, yellow and bi-color corn, while the rest of the acreage grows green beans, squash and broccoli.

Besides pests, there are also diseases to worry about, such as the common and southern rust, and the Northern and the Southern corn leaf blight.

"We use fungicides when blights and rusts appear," said Sanchez who explained that with blight, kernels don't reach their potential, while with rust, the plants lose their greenness and become weak.

"In addition to fungicides, there's also sanitation and other cultural practices, as well as resistant varieties as available," said McAvoy.

However, what is impossible to control is the weather. Frosts and freezes — including the most recent in early January — and heat and drought can impact quality or ruin crops.

According to the National Oceanic and Atmospheric Administration, La Niña is expected to continue through this winter. The condition brings on warmer than normal temperatures in the Southeast and cooler than normal temperatures in the Northwest.

"Drier weather can result in drought and water shortages, especially when Lake Okeechobee falls to critical levels and the South Florida Water Management District institutes water allocation reductions," said McAvoy.

Adequate water is important for the growth of sweet corn, especially during periods of silking and tasseling and of ear development.

"We use wells and other sources of water and pump it in," said Sanchez, who plants corn virtually all year long.

"Irrigation, primarily by furrow, a.k.a. 'seepage irrigation,'" is also used, said McAvoy, who mentioned that some growers in Homestead use big gun sprinkler irrigation.

Unfortunately, La Niña's warmer, drier temperatures may mean, especially for later planters, a disappointing yield.