In Japan autumn is good for dry and air kimono(Japanese traditional cloth) to protect it from mold and insects. High quality kimono is made of silk. Silk is not appropriate to be washed often, and vulnerable to mold and insects. So people put kimono in special drawers(→drawers for kimono) and dry it regurally in autumn and winter.
In the top drawer we put kimono which we wear rarely and wear at the event we do not expect it happen often.
That is mourning dress.
Japanese mourning dress is called Mofuku which is made of solid black cloth. Other items we put on are also black, obi(belt for kimono) and zori(shoes for kimono) and bag. Only nagajuban(underwear for kimono, a white collar sewn on it is shown) and tabi(socks for kimono)is white.
Some people wear white Mofuku which used to be more popular than black mofuku before Meiji era(1868~1912).
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