The September corn contract on the Chicago Board of Trade settled up 17-3/4 cents at $4.36-3/4 a bushel.

The August contract for soybeans settled up 10 cents to $8.89-3/4 a bushel, regaining some ground after falling 1.1 percent on Tuesday.

September wheat future prices settled up 10-3/4 cents at $5.14 a bushel.

"The past few days have been bearish for wheat and traders are going short with the holiday approaching," said Brian Basting of Advance Trading.

CBOT grain markets will be closed on Thursday for Independence Day.

The US Department of Agriculture (USDA) on Monday pegged the condition of the corn crop at 56pc good to excellent, unchanged from the previous week. Analysts polled by Reuters had expected a slight improvement.

A year ago, 76pc of the corn crop was rated good to excellent.

On Friday, the USDA surprised traders by estimating US 2019 corn plantings at 91.7 million acres, higher than expected, causing prices to tumble. Analysts had been expecting the acreage report to show farmers had planted 86.6 million acres of corn.

Dealers said prices had recovered some ground after falling sharply during the last few days, but the mood remained bearish with harvests in the United States and Russia making good progress.

There remained, however, some corn and soybean crop concerns after major flooding in the US Midwest delayed plantings.

"Uncertainty comes with July weather," said Basting. "Rain and cooler temps are extra reason to be concerned this year."

Weather forecasts are generally favorable, with no real threats on the horizon, Matt Zeller of FCStone said in a note.

Dealers noted Egypt was able to buy 60,000 tonnes of Romanian wheat at a low price earlier this week and the market's focus had now shifted to an Algerian tender which is due to close on Thursday.