Women proposing on February 29th dates back to when the date was not recognised, so had no legal status. This 'loop hole' date was chosen by women who felt they had been 'left on the shelf' too long.
In the 1500's most people got married in June because they took their yearly bath in May, and they still smelled pretty good.. However, since they were starting to smell, brides carried a bouquet of flowers to hide the body odor. Hence the custom today of carrying a bouquet when getting married