Men and flowers: from tradition and meaning to modern marketing and social norms.
The History of the Men's Bouquet

The tradition of giving flowers to a man came to us from the East, more precisely from Japan, where the art of ikebana gave rise to many traditions and customs related to the act of presenting flowers. For example, a child's anniversary—a holiday traditionally important across Asian countries—is always accompanied by a floral arrangement for the occasion. Considerable attention is paid to the bouquet's symbolic meaning, and giving flowers to men in the East has always been commonplace.
Civilized Europe had nothing to do with this refined custom until the mid-twentieth century, when men, for better or worse, also began to be given flowers. Today it is fairly easy to buy a bouquet for a man, since online catalogs—the most accessible and efficient—offer a truly wide selection of bouquets for all genders, ages, and occasions, and yes, these catalogs include a separate category of flowers for men.
Incidentally, in ancient times in the classical world flowers were presented to rulers as a sign of submission and respect. For example, in Greece an olive branch was always given along with the keys to a city upon surrender, and a laurel wreath and a bouquet of irises for the victor of the Olympic or Delphic games were the most important awards for athletes and poets. That is why the modern custom of giving flowers to men is in most cases still associated with some achievements and successes of the man, and giving a bouquet to a man without reason feels somewhat improper. That is, if a man receives flowers from another man... Everything, however, was allowed to a woman: in ancient times women gave flowers to a man as a sign of special attention, and the re-gifting of flowers received from one suitor to another carried even more significance. This indicated the highest degree of a woman's interest in a man, but almost always led to bloodshed, since a woman by definition could not insult a man, and suitors of the past took out their anger on their rivals.
Men's bouquets became a norm only in the twenty-first century, when specialization forces the marketing departments of every single company to split the customer base into segments by the most diverse criteria in order to form new consumer audiences. This is a rather base and philistine way for the custom of giving flowers to men to become everyday, but at least thanks to it a man can now also feel joy from receiving a bouquet of flowers, and flower delivery services can bring him that bouquet.