Why is the Chinese calendar based on the sun’s movement?

Flower cycle

Plant in the spring
Bloom in the summer
Die in the autumn (harvest)
Wait till winter passes

Next spring …

Human cycle

Start doing more exercise in the spring
Work hard in the field during the summer
Slow down and eat more in the autumn to prepare for the winter

Rest and sleep more in the winter – Next spring …

Farmers

Planting and harvest follow solar terms to take advantage of
rainfall and sunlight, and prepare the crops for dew and frost.

Traditional medicine

In traditional Chinese medicine (TCM), certain therapies are
synchronised with solar terms. For example, in moxibustion, the
application of heat on the skin surface is believed to transmit
energy to the body to cure various diseases or disorders.

This is called “curing winter diseases in summer and summer
illnesses in winter” and is meant to enhance the therapies. TCM
also recommends various soups, infusions and other preparations
throughout the year based on the position of the sun.

Fishing

For fishermen, the end of the heat means harvest time. During this
period, fishing season festivals are held along the coast of the
East China Sea in Zhejiang province, near Shanghai. Because of the
higher sea temperatures, a lot of fish leave the deep waters and
come closer to the surface.

Diet

People should eat the right combination of foods – based on the
weather – to keep their bodies functioning harmoniously.
Traditional recommendations include: “Eating buds in spring, melon
in summer, fruits in autumn and roots in winter” and practising
intermittent fasting.

Solar terms and ancient China

The idea of solar periods dates back to the Shang dynasty (1600 BC
to 1046 BC), deriving from the need to have a precise climate
reference to optimise agricultural production.

The ancient Chinese believed the weather changed every 15 days.
The year was divided in 24 solar terms. Tradition has it that
farmers saw how the time of year affected insects, plants,
rainfall and the length of days, among other essential factors for
farming activities.

Scholars from the Yellow River basin, the birthplace of Chinese
civilisation, established four solar major terms. During the Zhou
dynasty (1046 BC to 256 BC), this was increased to eight, then,
during the Han dynasty (202 BC to AD220), the current 24 were
established, beginning with the “start of spring” and ending with
“major cold”. Each season was divided into six solar terms, each
lasting 15 days.

Solar terms, seasons, and dates

The following is a detailed explanation of seven of the 24 solar
terms, when changes in the environment and nature are more
noticeable. These changes are the origin of traditions that have
been celebrated for centuries in China and other countries
including Korea (24 jeolgi), and Japan (24 sekki).

Here are the dates and seasons for these seven solar terms in
2023: