Why did Hankou become a major centre for tea trade in the 19th century?

Hankou became a major center for the tea trade in the 19th century primarily due to its strategic location and its designation as a commercial port. Following China's defeat in the second Opium War, Hankou was opened to Western nations in 1861, which facilitated its development as the head of international oceangoing traffic on the Yangtze River.1

Leveraging the facility of communications provided by the river system, the city became a vital hub for the collection and processing of goods. For the first 20 years after its opening, trade in the region was based almost exclusively on tea. This status as a primary commercial gateway allowed Hankou to thrive as a business center, building upon its long-standing history as one of the four most famous towns in China during the Ming and Qing dynasties.12