Legendary investor Jim Rogers says commodity investors should pay close attention to the turmoil in Ukraine, "if for no other reason than the fact that both Russia and Ukraine are huge commodity producers."

"Ukraine especially is a large agricultural commodity producer and has been for centuries, and it’s been awfully good at it for centuries," Rogers told HardAssetsInvestor.com. "I don’t know if this is going to disrupt production or not, but if it does, that is just that much less supply on the market."

Rogers isn't surprised that prices of agricultural commodities have risen recently. "Inventories of agriculture products are near historic lows," he said. "The world has consumed more than it has produced for a decade now, and we’re running out of farmers worldwide."

So what's going to happen?

"We’re expecting a crisis in agriculture sometime in the next few years, and prices are going to go much, much higher," Rogers said.

Editor's Note: Investing Secrets That Profit 96% of the Time (Free Video)

Meanwhile, Rogers said he is biding his time on gold, and that there probably will be an attractive time to buy in the next year or two.

"If that means gold is under $1,000, I hope I’m smart enough to buy. If it means gold is $1,600 because America and Iran end up going to war, I hope I’m smart enough to buy it," he said.

June gold futures settled at $1,308.60 an ounce on the Nymex Tuesday, down 70 cents from
Monday. Gold has advanced 8.6 percent so far this year after plunging 28 percent in 2013.

"In my view, it’s more likely there will be another chance to buy gold lower than now, and that’s why I’ve hedged some of my gold, but I’m not selling."

When it comes to stocks, some are undoubtedly overvalued, Rogers said. "We might have seen bubbles develop in some sectors such as biotechnology. You see what has happened to those stocks," he said.

"There may even be bubbles in some other sectors like social media and technology. . . . But the whole market is not a bubble. It may be too expensive, but an overpriced market is different from a bubble."

With U.S. stocks so close to record highs, Rogers said he wouldn't buy them. Both the S&P 500 and Dow Jones industrial average are within 2 percent of their all-time peaks. "There are other markets around the world that are certainly much cheaper on a historic basis," Rogers said.

Many other experts express caution about U.S. stocks, too. Job gains alone won't be enough to push them higher, Scott Clemons, chief investment strategist at Brown Brothers Harriman, told The Wall Street Journal.

"It will take some catalyst, a genuine acceleration in economic activity or a sign that corporate America can expand profit margins from already record-high levels," he said. "I am hard-pressed to see a whole lot of catalysts."

Special: Free Today - Get 'The Richest Man Who Ever Lived'

Related Articles:

• Investor Jim Rogers: 'This Is the Time to Buy Russia'
• Jim Rogers: 'We Should Be Terrified' Because Fed Tactics Will 'End Badly'