Wheat rose for a second session as drought in the US Plains remained a focus, while corn also edged up.
The Chicago Board of Trade most-active soybean contract had added 0.85 percent to $10.41 a bushel by 1214 GMT after falling to $10.27 a bushel, its weakest since Feb. 21.
Wheat gained 0.4 percent to $4.90-3/4 a bushel and corn rose 0.3 percent to $3.89-3/4 a bushel.
"Markets are still undecided between ample supplies and climatic risks in America underpinning prices in Chicago," consultancy Agritel said in a note.
An annual survey by brokerage and analytical firm Allendale Inc on Wednesday estimated US farmers would plant a record 92.104 million acres of soybeans in 2018, well ahead of 88.514 million acres expected for corn.
The survey dampened soybean futures on Wednesday and put attention back on large global supplies of grains and oilseeds.
However, drought in Argentina remained in focus, with rain forecast for this weekend expected to be too late to significantly revive yield potential.
The soybean market has also been assessing the risk of fallout from trade tensions between the United States and China.
"The worries about US-China soybean trade have no doubt helped persuade some that holding a long position real or de facto - is not a good idea," said Tobin Gorey, director of agricultural strategy at Commonwealth Bank of Australia.
The wheat market is being underpinned by expectations of a lower US crop.
The governor of top wheat state Kansas declared a drought emergency in 28 counties and issued drought warnings and watches for the rest of the state.
Like in Argentina, some rain forecast in the week ahead in the US hard red winter wheat regions was not expected to make a meaningful difference to crop conditions.
Grain markets are also waiting for weekly US export sales for a fresh indication of demand.
In wheat, results are also pending in a tender by major wheat importer Egypt. Black Sea origins again dominated offers in the tender, with US and west European wheat not offered.