Corn Crop Planting and Harvest Seasons

There several factors that go into determining corn prices

Corn on the stalk
••• Wesley Hitt/Photographer's Choice/Getty Images

Corn crops around the world have different production cycles when it comes to planting and harvesting timeframes. Analyzing the corn market requires an understanding of the planting and harvest seasons within each country. Grain prices tend to fluctuate the most during growing seasons, as supply expectations can shift significantly as a result of planted acreage, weather, and growing conditions.

Where Corn Crops Tend to Grow

In the United States, most of the corn crop grows across the fertile plains of the Midwest. Typically, the southernmost areas will begin planting first, and the most northern regions plant when the snows melt and the soil thaws. The major growing areas of the world are as follows:

  • United States
    Planting: Begins in April and continues through June
    Harvest: Commences in October and finishes by the end of November
  • China
  • Planting: Begins in mid-March through early June
    Harvest: August through October
  • European Union
  • Planting: Mid-April through early June
  • Harvest: Mid-August through late October
  • Brazil
    Planting: Early August through November
    Harvest: February through May
  • Argentina
    Planting: October through November
    Harvest: March through May

Corn's Importance as a Crop

Corn is an incredibly important crop around the world. Though it is a staple foodstuff, with the world’s largest producing and exporting nation, the United States, corn is the main ingredient in the production of ethanol, a gasoline additive. Each year the annual corn crop determines the price of the grain. 

Farmers often use the futures market to hedge the price of corn throughout the growing process. The December futures contract, traded on the Chicago Board of Trade division of the Chicago Mercantile Exchange, is the new-crop contract. During growing season, farmers will often sell the December futures contract to hedge or lock in the price of corn that is growing and not yet ready for harvest.

During the harvest season, the farmers will sell their physical crop and close out their short futures positions by purchasing them back thus closing out the hedge. 

The difference between the price of December corn futures and the physical price of corn at a terminal or silo is the basis. The basis is one of the many risks that farmers take. However, the risk of the difference between physical corn prices and the new-crop futures contract is often much less than the actual corn price given the price volatility of the grain.

How Corn Prices Are Determined

The key determinate of corn prices each year is the weather across the growing regions in the world’s largest producing nation, the United States. Other factors that contribute to price volatility in corn are ethanol prices, crop yields in other producing countries and the relative value of the U.S. dollar.

When the dollar appreciates, corn becomes more expensive in other currencies. Corn buyers around the world will seek other sources of corn as U.S. based corn becomes less attractive on the global markets and U.S. exports decline. Conversely, when the value of the dollar decreases the price of corn declines in other currencies and the demand for U.S. corn increases making U.S. exports more attractive.

How Farmers Choose Which Crop to Plant

Farmers often have choices of which crop to plant on their land each year. Therefore, the price of soybeans is often a factor in the corn crop. When soybeans become more expensive than corn on a historical basis, farmers tend to plant more beans and less corn.

Conversely, when corn is historically expensive compared with beans, the producers tend to plant more corn. 

What Influences the Price of Corn

Each year, the price of corn is a function of the ultimate size of the crop in the United States. Inventories, or carryover, from recent crop years, also can influence the price of corn. The larger the carryover is, the less likely that corn prices will appreciate dramatically.

Large inventories of any commodity point to a condition of oversupply. However, when supplies in storage facilities are small, a deficit can develop and when available supplies cannot meet demand the price of corn can rise rapidly.

There are many factors that go into the ultimate price of corn each year. The most volatile season is the period between spring planting and fall harvest in the U.S., as this is the time of the year when there is the greatest uncertainty about the size of the final crop.