Gardener's Dictionary: Phototropism
Phototropism (n): The movement of a part of a plant toward or away from a light source. Sunflowers are heliotropes, and their flower heads follow the sun throughout the day.
Phototropism (n): The movement of a part of a plant toward or away from a light source. Sunflowers are heliotropes, and their flower heads follow the sun throughout the day.