DAY OF THE DOUBLE FIFTH

The Dragon Boat Festival is also known as the day of "Double Fifth". This period is around the summer solstice which falls on June 21.

The "Double Fifth” Day
The ancient Chinese believe that the fifth lunar moon or month is a pestilential and danger-fraught period. The fifth month was considered an evil month and it was an especially bad omen to be born on the fifth day. It is said that children born in this month are difficult to bring up, bringing his/her parents much grief. This was the month during the hot summer when the weather was most conducive to diseases brought on by the " Five Gods of Plague". In ancient China, the people tend to concentrate their efforts during this time attempting to protect their families from ills and misfortune.
According to custom, the double fifth day is the time when cleaning and sanitation are stressed. Most families hang calamus and artemisia above their doors, both as a decoration and as a preventive against pestilence. There is an old saying to the effect that "a disease of seven years can be cured by three years of artemisia".
To further combat against ills and inauspice, protective charms were developed. One of the charms was by wearing five colour threads or ribbons of silk. These "threads of life" were given as gifts to families for the purpose of averting bad influences. The five coloured ornaments can be worn in the hair. Originally the zongzi was tied with five coloured threads. I'll blog more about this in another post.
Another charm is the "Five Poisons" (WuDu) motif. The animals represented are the snake, centipede, scorpion, lizard, and toad ( sometimes the spider replaces one of these creatures). Their images are embroidered on clothing, stamped on cakes, and engraved on paper.
Similar to hanging artimesia, anothr method involved hanging a bouquet of four types of green leaves and on posy of flowers ( to make five) over doorways to ward off demons. Mugwort leaves, calamus, and garlic were also hung over doors to ward off poisionous influences. And lastly portraits of Zhong Kui, a demon-stayer, or pieces of paper (fu) with anti-demonic incantations were posted outside and around the house.
Ancient folk medicines such as realgar are added to the food eaten on this particular day. This is believed to prevent disease and to promote a healthy digestive system. The drinking of realgar in wine supposedly relieves the effects of poisons accumulated in human bodies. The Chinese also eat food like garlic, pickled vegetables, greens and yellow croaker (a type of fish) which they believe to have medicinal value.

I also read that in olden times (maybe even now) some of the protective measures taken on the double fifth day include, the painting of the ideograph Wang (King) on the foreheads of children with cinnabar, and the fastening of amulets containing spices or medicines to the buttons of their clothing. The spices or medicine are put in sachets (Hsiang Pao in Mandarin) are popular with children. These Hsiang Pao are also given to older people as a symbol of respect. These sachets have intricate and beautiful embroidery sewn on them.

References:
http://www.sandiegochinese.net/htmls/dragboat.htm
http://www.goodlucklife.com/excerpt.html