I don't have much information for you. Just that there are two keys to any new on-line business:
1. Advertising. If no one knows you exist, you will never get customers.
2. Differentiation. You need to give potential customers a reason to stop shopping somewhere they feel comfortable, and to shop with you instead. The more significant your differentiation, the stronger the reason. Of course, this gets tricky, because if you are too different, then no one will buy from you because you don't have what they want.
For example, if you were to offer custom tea blends, that might just be enough to draw some people to you. Offering a lot of high-quality individual flavorings and herbs is another thing to consider. Or offering customized tea pots/mugs/etc. These are just thoughts, here, I make no guarantees they would work and/or are plausible.