As spring equinox approaches, the day and night balance across the globe. In the Chinese traditional calendar, spring equinox, or Chunfen in Chinese, is the best time to go outdoors to fly kites. Also, people cook sprouting vegetables to welcome a season of renewal and rebirth.

Falling on March 20, Chunfen is the fourth of the Twenty-four Solar Terms following Awakening of Insects about half a month ago. Usually, Chinese people do farm work based on the solar terms. However, Chunfen is one of the few solar terms that has little relevance to agriculture, according to Nie Yuanlong, an expert on traditional culture.

Chun in Chinese means spring while fen refers to divide the spring. It signals half of the season. After Chunfen, daytime gets longer and warm weather heralds colorful landscapes.

"People in different places have different traditions to celebrate Chunfen. They often go out to take part in various activities to enjoy the good weather and also have fresh vegetables on their tables," Nie says.

For kite makers like Yang Liping, Chunfen is the best time to fly them. Since he was a little boy, it was a tradition for him and his friends to fly kites on Chunfen because the wind is stable and kites can easily soar.

Yang is good at making swallow-shaped kites, a typical type of kite in Beijing. In ancient Chinese poems, poets described the migration of swallows from south to north in spring.