Sanqingshan's upper slopes host extensive natural rhododendron populations that bloom from late April through May, carpeting the terrain beneath the granite formations in shades of pink, red, and white. The Sanqingshan rhododendrons grow as proper trees rather than shrubs — individual specimens reach four to five metres and the canopy of bloom against the grey granite background is the combination that brings photographers to the mountain in spring.
The best concentrations are along the South Gate circuit between the ropeway station and the Sanqinggong temple area. The timing varies slightly year to year depending on temperature and rainfall, but late April through the first week of May is the reliable window. The mountain is noticeably more crowded in rhododendron season than at other times; weekday visits are significantly more peaceful.