Herb bag

Herb bags are a specific type of bag that allows the storage of herbs gathered by characters of the herbalism profession. Herb bags cannot carry vials and are all Bind on Equip.

There are 6 known sizes: 12 slot, 20 slot, 24 slot, 28 slot, 32 slot, and 36 slot. The 20, 24, 28, 32 and 36 slot varieties are crafted by Tailors; they require, respectively, and  reputation with the Cenarion Circle,  reputation with Sporeggar, and  with The Kalu'ak in order to obtain the patterns, but no reputation needed to learn the 36 slot bag. There is also no reputation requirement to simply equip any of the bags.

Herb Pouch (12 Slot)

 * Sold by Herbalism Supplies vendors. Being a green item, they are often sold on the Auction House at a high markup.  Be careful!

Cenarion Herb Bag (20 Slot)

 * Requires 275 Tailoring
 * Requires Cenarion Circle,
 * 5x Bolt of Runecloth
 * 10x Purple Lotus
 * 2x Rune Thread

Satchel of Cenarius (24 Slot)

 * Requires 300 Tailoring
 * Requires Cenarion Circle,
 * 6x Bolt of Runecloth
 * 2x Mooncloth
 * 1x Black Lotus
 * 4x Ironweb Spider Silk

Mycah's Botanical Bag (28 Slot)

 * Requires 375 Tailoring
 * Requires Sporeggar,
 * 4x Primal Mooncloth
 * 2x Fel Lotus

Emerald Bag (32 Slot)

 * Requires 435 Tailoring
 * Requires The Kalu'ak,
 * 4x Moonshroud
 * 6x Frost Lotus

Hyjal Expedition Bag (36 Slot)

 * Requires 490 Tailoring
 * 20x Bolt of Embersilk Cloth
 * 40x Volatile Life

Other items
Herb bags can fit some other items that are not collected solely by Herbalists:
 * Blood Scythe
 * Glowcap
 * Unidentified Plant Parts
 * Night Dragon's Breath
 * Packet of Tharlendris Seeds
 * Morrowgrain
 * Whipper Root Tuber
 * Enriched Lasher Root
 * Primal Life
 * Mote of Life
 * Eternal Life
 * Crystallized Life
 * Volatile Life
 * A Druid's Rebirth reagent seeds: Maple Seed, Stranglethorn Seed, Ashwood Seed, Hornbeam Seed, Ironwood Seed