* Market expected Argentine corn to be available in March
* Experts now say bulk of harvest to take place in May, June
* About half the country's 2012/13 corn seeded so far
* Planting lags last year's pace by 12 percentage points
* Argentina is world's No. 2 corn exporter after U.S.
By Hugh Bronstein
BUENOS AIRES, Nov 26 (Reuters) - Flood-hit Argentina will harvest corn later than expected this season, supporting already-high world food prices as consumer nations are forced to rely longer on thin U.S. supplies.
Argentina is the No. 2 corn exporter after the United States, where the worst drought in decades trampled this year's crop. With food stocks hit by dry weather in breadbaskets Russia and Australia as well, importers are looking to South America.
But Argentine growers have said they will produce 20 percent less corn than initially forecast due to excessive August-October rains that turned prime Pampas farmland into unplantable mush.
The United States was already set to dominate the corn market through March, when the Argentine crop had been expected. With wide areas of the Pampas still waterlogged, it looks as if consumer nations will have to rely on U.S. supply until May or June, local growers and industry experts say.
Much of Argentina's 2012/13 corn will go into the ground in December, three months later than usual.
"May and June will be the peak harvesting months this season," said Martin Fraguio, executive director of Argentine corn industry chamber Maizar. "The total 2012/13 harvest looks like it will be somewhere between 25 and 28 million tonnes."
That will not come close to filling the gap left by a U.S. corn haul chopped by drought to 272 million tonnes, or about 100 million tonnes under early-season forecasts. The previous U.S. harvest was 323 million tonnes.
Chicago corn futures are up 16 percent this year as part of a global grains rally driven by low supplies.
Aside from raising fears that developing countries will not be able to afford basic staples, the rally is fueling inflation in advanced nations, making it harder for them to keep interest rates low enough to breathe air into their sluggish economies.
PAMPAS RAINS NORMALIZING
The weather in Argentina has normalized over recent weeks and farmers hope their fields will dry out enough to let them seed genetically modified (GMO) corn designed to withstand the bugs that attack crops as the Southern Hemisphere summer gets under way in December.
The trend toward late sowing is here to stay, thanks to GMO technology and new tilling techniques that increase efficiency, said David Hughes, who manages 3,000 hectares (7,400 acres) in the key farm province of Buenos Aires.
"The futures market is telling us that buyers still expect most Argentine corn to come in March. But it's not going to be that way this year. My forward contracts are open into July because everything is delayed by the floods," Hughes said.
Last year, he planted 30 to 40 percent of his corn in December. In 2012, he said, 70 to 80 percent will go into the ground in the last month of the year.
Hughes became a fan of December corn sowing last season, when his late-planted GMO seeds yielded better than early-planted fields hit by a December-January drought just as plants were entering their delicate flowering period.
Some commercial pressure has been taken off Argentine farmers this year thanks to a new government policy of announcing full-season quotas for corn exports. The scheme replaced an incremental quota system that growers said hurt their profits by reducing competition among buyers.
The government announced in September that 15 million tonnes would be freed for export this season. Argentina curbs exports to ensure ample domestic supplies of food.
"No one is in a hurry to plant or sell corn this season because of the new, one-shot quota system and the fact that more December planting has been made possible thanks to advances in technology," Hughes said. "All the floods did was push us faster in a direction we were already going."
Other growers are embracing December planting as well. Only about half the 3.4 million hectares expected to be sown with 2012/13 corn in Argentina has been seeded so far, lagging last season's planting tempo by 12 percentage points, according to a local grains exchange.
Two years ago, Santiago del Solar, who manages 12,000 hectares, started experimenting with late-planted GMO corn in an effort to spread out weather-related risks. He found little difference between early- and late-planted corn yields.
"This year we are planting more in December because soils were not firm enough to plant earlier," said del Solar, who plans on sowing 25 to 30 percent of his corn in December versus 20 percent last season.
Soybeans and derivatives such as soyoil and meal are Argentina's main farm export. In times of bad weather, growers tend to switch from growing corn to soy, which is relatively cheap to plant and more resistant to adverse conditions.
The extent to which soy area will rise at the expense of corn will not be known for at least another month, when growers can survey how much land they ended up planting despite the torrential Southern Hemisphere spring rains.
"A lot of acreage will just stay flooded this year, so it won't go to corn or soybeans," del Solar said. "It will just stay flooded."