Stormvine is the second herb you will be gathering in Vashj'ir if you have Herbalism with my 10k an hour Farming Guide. As I have mentioned before you don't really need Herbalism for farming here, Mining is the better of the two, however Herbalism will double the income you will be making in the short 5 minutes you spend swimming around gathering stuff here. Much like Azshara's Veil I load the Auction House up with a few stacks of Stormvine, depending on that day's economy and then I will branch out from there if needed.
Also, again, much like Azshara's Veil you will be able to drastically expand the amount of players you can market to your wares too with just two simple Tradeskills, Inscription and Alchemy. This is far from a requirement to farming here and in fact if you really wanted to you could just find someone else to make them for you. To start I will show you what you can have a player with Inscription make for you.
That is all you can turn Stormvine into through Inscription, or at least all that is worth it. Now it may not seem like much and you may be wondering what the conversion ratio is for doing this. On average you will recieve a few Ashen Pigment with each mill and a chance for Burning Embers. Ashen Pigment can be turned into Blackfallow Ink which goes for 90 - 120g a stack depending on the day/your server. The Burning Embers can be turned into Inferno Ink and sold for roughly 70g each.
It would be impossible to tell you how many Ashen Pigments and Burning Embers you will get because it is really completely random. Sometimes a single stack of Stormvine will yield 2 or 3x more than it's value if you didn't mill it and sometimes you will get less. Now it is time for what you can turn Stormvine into with Alchemy. Unlike Azshara's Veil there are two potions that I have found useful to make with Alchemy that require Stormvine as a reagent.
One of them is an Earthen Potion, which is a popular potion amongst tanks and the other is a Potion of the Tol'vir which is a popular potion amongst agility users. Now since these potions are both commonly used in raids, specifically raids that are hard for certain guilds that need a little boost to beat it. This means these potions will sell the best when most of the guilds on your server are learning content and trying to progress. So usually at the start of any patch that adds new raid content is when these potions will sell the best.