Square Enix has released patch 2.3 for Final Fantasy 14: A Realm Reborn today which adds the ability to raise chocobos to the game.
On the MMO's website, the publisher has provided some details on how this works. In order to raise chocobos, players will need to be level 30 and complete the Bird in Hand Quest in order to access chocobo stables and begin raising the feathered mounts.
Players will also need to have completed the quest My Feisty Little Chocobo and belong to a free company which owns an estate in order to take advantage of this new mechanic.
Chocobo stables can be purchased from any housing merchant in a residential area. After you've placed the stable, all free company members can stable their chocobos there and begin training them. You won't be able to mount a chocobo or summon them in battle while they're stabled.
Chocobos can be trained once per hour and require a reward of one of the following: Krakka Root / Curiel Root / Sylkis Bud / Mimett Gourd / Tantalplant / Pahsana Fruit / Thavnairian Onion.
Giving a chocobo a Thavnairian Onion will allow you to train it even after it's hit the level cap.