Inside a greenhouse in Maldrogungkar county, Lhasa, Meng Deli runs his hand over a row of crops, stopping to check leaves, moisture, and temperatures. Around him, fruit and vegetables grow in lines-a far cry from the winters when the locals lived largely on cabbage, radish, and potatoes.

Meng is a senior agronomist from Shouguang, Shandong province. He was first invited to help improve vegetable production in the Xizang autonomous region in 2016 after years of agricultural work in northern China.

He arrived with 60,000 yuan (about $8,700) and five workers, and decided to stay. Nearly a decade later, his team's work has become part of a bigger story, expanding the range of produce grown at altitude while passing on techniques that are gradually taking root.

The project did not begin smoothly. The team had to work through altitude sickness, a shortage of supplies for building greenhouses, language barriers, and harsh weather. Meng recalled a time when the team was helping to build the region's first large greenhouse of its kind in Panam county, Shigatse. A sudden Force 12 gale hit the newly-built structure, injuring three workers.

"That night I really thought about giving up," Meng said. But after three days of trying to work out what had gone wrong, the team started again. To cope with plateau conditions, they narrowed the spacing of greenhouse film from two meters to 90 centimeters, developed ultraviolet-resistant plastic that could last years, and introduced double-layer film, insulation quilts, and automatic rolling systems.

That trial-and-error process helps explain what Meng and his colleagues call the "Shouguang model". The team introduces a complete greenhouse farming system with seedling cultivation, pest control, temperature management, crop timing, and irrigation and fertilizer planning. They adjust the process to local soil, wind, and ultraviolet exposure.

If Meng sets the overall direction, Zhang Yuxiang, a lead technician, helps turn that system into daily practice. Zhang said much of his work was hands-on, such as showing local workers when to ventilate, when to water, how to spot seedling problems, and how to manage crops through changing temperatures. Seedlings were often donated free of charge.

"We teach the local farmers on-site because of language barriers," said Zhang. "Repeated demonstrations in the greenhouses were often more effective than explanation alone." He also said he continued to guide growers in other places by phone and video calls.

The impact becomes clearer in the voices of residents.

Wangmo, who works at the Maldrogungkar base, said people in the area had once grown mainly potatoes and radishes. "Now, through working in the greenhouses, we learned how to grow more vegetables, including Chinese cabbage and green peppers," she said.

"Vegetables used to be scarce in local diets," said Samtan, another local worker. "Now, you can eat whatever you want."