"Why don't you get a haircut? You look like a chrysanthemum"

This quote by P. G. Wodehouse is a humorous way of recommending that the individual's hair is too long and unkempt. It implies that the person's hair is so long and wild that it looks like a chrysanthemum, a flower with lots of petals. The speaker is recommending that the person needs to get a haircut to make their hair look more nice.

The quote is likewise a subtle way of expressing disapproval of the individual's look. It indicates that the person's hair is not well-groomed and is not in line with social requirements of beauty. The speaker is suggesting that the individual must take better care of their appearance and get a haircut to make themselves look more appealing.

The quote is humorous because it is an unanticipated contrast. It is not typical to compare somebody's hair to a flower, and the comparison is unexpected and amusing. The speaker is using humor to make a point about the individual's look in a lighthearted method.