How do sunflowers track the Sun?

Sunflowers track the Sun through a process called heliotropism. During the day, young sunflower heads move to face the Sun, maximising their exposure to sunlight for photosynthesis. This movement is controlled by specialised cells in the stem that elongate on one side, causing the flower to tilt. As the sunflower matures, it stops moving and permanently faces east, optimising pollinator visits in the morning. This behaviour ensures efficient energy capture and reproductive success.