About 20 to 25 percent of Rainbow Farm's products supply the hotel's Yue Chinese Restaurant. Suburbanites and downtown dwellers buy the rest. The farm delivers sufficiently large orders to residents' doorsteps.

Provided to China Daily

"It can't provide for all of the hotel's need because we can't grow some species," Guo says.

"So, the output is limited."

He says increasing diversity decreases output.

For example, melons takes 40 days from planting to harvest.

It takes patience and skill to run an organic farm. Rainbow is run by 10 workers, six of whom are local farmers.