HARARE, Zimbabwe — When Roger Boka started his auction business in the 1990s, this city’s tobacco trading floors were hushed places, save the mellifluous patter of the auctioneer. A handful of white farmers, each selling hundreds of bales of tobacco, arrived in sport utility vehicles, checking into the city’s best hotels while waiting for their big checks to be cut.

During this year’s auction season, a very different scene unfolded underneath the cavernous roof of the Bock Tobacco Auction Floors. Each day, hundreds of farmers arrived in minibuses and on the backs of pickup trucks, many with wives and children in tow. They camped in open fields nearby and swarmed to the cacophonous floor to sell their crop. The place was lively and crowded; two women gave birth on the auction floor. The most obvious difference, though, was the color of their faces: every single one of them was black.

“You used to only see white faces here,” said Rudo Boka, Mr. Boka’s daughter, who now runs the family business. “Now it is for everybody. It is a beautiful sight.”

Before Zimbabwe’s government began the violent and chaotic seizure of white-owned farms in 2000, fewer than 2,000 farmers were growing tobacco, the country’s most lucrative crop, and most were white. Today, 60,000 farmers grow tobacco here, the vast majority of them black and many of them working small plots that were allotted to them in the land upheavals. Most had no tobacco farming experience yet managed to produce a hefty crop, rebounding from a low of 105 million pounds in 2008 to more than 330 million pounds this year.