The corsages traditionally identify the special female family members of the ceremony, namely the mothers and grandmothers of the bride and the groom, and the maid of honour.
Below are a few points worth considering should you choose to have them.
First of all, prices range considerably. Thus if you are confined to a specific budget you should go for a simple design or limit the corsages to the mothers only.
How is a corsage worn? There are three traditional ways to wear a corsage. The first way is to pin it to the left lapel of the dress, sometimes extending over the shoulder. Alternatively it can be pinned to a purse or worn around the wrist. Whichever way is chosen the corsage should match the colour scheme of the dresses.
Generally the corsage is slightly larger than the boutonnieres worn by the gentlemen, but limited to a size that does not become too heavy to wear. If the design is disproportionate, real flowers can pull on the fabric of a dress. When a dried or silk arrangement is worn, be especially careful to guard against damage to the design itself, especially at the point where it is attached.
Another option, instead of a corsage, is to use a single rose or tiny bouquet tied with fine silk and ribbon. It is also a consideration when looking at cost and actually popular because it is very effective in wedding photographs.
Should costs permit, while a corsage is intended for family members, you may wish to use them as a token of thanks to special friends. The courtesy may even be extended to the other individuals directly involved in the ceremony, such as the readers, and the soloist or musicians.
Photo by Tai Gray from Provo, USA (Corsage Uploaded by France3470) [CC BY-SA 2.0 (http://creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons