Sugar Cane + Light Source FPS issue

See screenshot.

In this situation, FPS drops dramatically when looking at this particular scene. Looking away will result in double to even quadruple the FPS. Even when looking directly behind me, which has a similar setup (a patch of Wheat with a similar water source and light source).

Tested with Mimap off/max; Advanced OpenGL off/on; Smooth Lighting Off/Max; Graphics Fast/Fancy – Nothing has any effect to improve FPS.

Sugar Cane scene: ~70 FPS
Surrounding environment: 140 - 300 FPS.