The most active corn contract for May delivery went up 1.25 cents, or 0.35 percent to close at 3.6275 dollars per bushel. May wheat delivery added 7 cents, or 1.51 percent to close at 4.71 dollars per bushel.
May soybean delivery was down 1.25 cents, or 0.14 percent to close at 8.9875 dollars per bushel.
Soybeans futures traded higher on Wednesday morning, as more investors showed optimism over ongoing trade talks between the United States and China.
The U.S. Department of Agriculture on Monday confirmed 828,000 tonnes of soybeans by private exporters for delivery to China during the 2018/19 marketing year.
However, soybeans started to retreat as investors turned to technical selling, as they are awaiting more details about ongoing trade talks between the two countries.
CBOT wheat futures rose 1.51 percent higher, with the market underpinned by short-covering, traders said.
Corn futures also closed firmer, as concerns about planting delays in the U.S. Midwest provided support to corn but massive domestic supplies kept the gains in check.
As for weather forecast for agricultural crop, melting snow continues to contribute to river flooding in several parts of the U.S. Midwest.
In North Dakota state, flood warnings already in effect may get worse as temperatures warm starting Thursday, according to the National Weather Service.