What is behind the winter radish proverb?

Winter radish and ginseng (proverb)

There is also a proverb about radish:

Radish and vegetables have their own tastes.

Eating radishes and drinking tea makes doctors crawl all over the street.

Radish and ginseng in autumn and winter eat radish in winter and ginger in summer without a doctor's prescription.

October radish and ginseng.

Ginger ate early, radish ate late, and Mr. Langzhong cried.

Radish is on the street, and there is no business in the pharmacy.

Radish is loud and crisp, and it can live for hundreds of years.

The pear of Yantai apple is not as good as the radish skin of Rugao.