CHICAGO, Oct 18 (Reuters) - U.S. corn futures climbed on Monday, rallying from early declines, as traders focused on fears of rising fertilizer prices restricting corn plantings in the coming year, along with stronger-than-expected weekly U.S. export inspections data, analysts said.

Soybean futures also rose, buoyed by strength in soyoil and global vegetable oil markets. Wheat futures followed the firm trend.

As of 1:08 p.m. CDT (1808 GMT), Chicago Board of Trade December corn futures were up 7 cents at $5.32-3/4 per bushel. November soybeans were up 6-1/4 cents at $12.24 a bushel and December wheat was up 3/4 cent at $7.34-3/4 a bushel.

Corn posted the biggest gains on a percentage basis as traders worried about high costs for fertilizer.

"Corn prices find support from declining yields and fears that acreage will decline globally due to high input costs in 2022," Arlan Suderman, StoneX chief commodities economist, wrote in a client note.

The market found additional support as the U.S. Department of Agriculture reported export inspections of U.S. corn in the latest week at 976,218 tonnes, above a range of trade estimates and the biggest weekly tally since early August. Soybean inspections also topped trade expectations at 2,298,315 tonnes.

Meanwhile, analysts surveyed by Reuters on average expected the USDA later on Monday to report the U.S. corn harvest as 54% complete, up from 41% a week earlier. The soybean harvest was seen as 62% complete, up from 48% the previous week.

Soybean planting is under way in the southern hemisphere. In top global producer Brazil, soybean planting was 22% complete by Oct. 14, the second-fastest progress as of mid-October, agribusiness consultancy AgRural said.

Soybeans drew support as soyoil futures advanced, following as Malaysian palm oil futures rose more than 1%.

CBOT wheat was modestly higher in technical moves, with underlying support from tightening world supplies.

"Wheat prices continue to find global mill buying on price breaks amid tight supplies among major exporters," Suderman said.

However, Russia, a top global exporter, may increase its wheat crop to 80.7 million tonnes in 2022 from 75.5 million tonnes in 2021, Sovecon, one of the leading agriculture consultancies in Moscow, said in a note. (Reporting by Julie Ingwersen in Chicago with additional reporting by Michael Hogan in Hamburg and Colin Packham in Canberra; editing by Chizu Nomiyama)