Short answer
For the river, late September to November: clear water, comfortable air, and reliable cruise departures. For the terraces, April–May for flooded paddies or late September–early October for gold. One window for both: late September to mid-October.
Two calendars, not one
The river and the terraces peak at different times. The river is best when rainfall drops and the water clears, usually late September through November. The Longji terraces are best in April–May, when the paddies are flooded and read as ribbons of water, or in late September–early October, when the rice turns gold before harvest.
If you want one window for both, aim for late September to mid-October. The rice is still gold, the river is usually clear, and the heat has broken. The catch is National Day (1–7 October), one of China's busiest travel weeks; shift a week earlier or later if you can.
The months to avoid
June, July, and August are hot, humid, and wet, with peak domestic crowds in July and August. The river can flood and cruises can be cancelled. Late June and early July are the riskiest for rain.
The first week of October and the Chinese New Year period are the busiest. If you dislike crowds, avoid those windows and book everything else around them. The when to go hub has the full month-by-month breakdown.
Match the month to the trip
For the river and the city, October to November is the most comfortable. For photography and atmosphere, April to May. For the terraces, April to May for water and September to October for gold.
The rainy season question explains the wet months, and the winter question covers December to February. If your dates are flexible, the festival calendar shows which lunar holidays will change the crowds.
Related questions
Field desk / direct line
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