This month marks the beginning of summer in Minnesota. June 20 is the summer solstice, when our planet is tilted so that the Sun shines on its northernmost point on Earth, the imaginary line known as the Tropic of Cancer, about 23° latitude north of the equator. We have longer hours of daylight than on any other day of the year. It is as if the northern hemisphere of the Earth has turned its face toward the Sun, welcoming its warmth and shining light. Certain plants and flowers also have a rhythm of turning toward the Sun, a phenomenon known as heliotropism. In the morning, young sunflowers are turned toward the east, anticipating the sunrise. Throughout the day, they follow the path the Sun traces in the sky, continually re-orienting and turning themselves toward the Sun’s shining light and warmth until sunset in the west. By constantly following the Sun, the young sunflower collects more energy for growing.