Direct marketers (and wineries that successfully market direct-to-consumer) know that "it's all about the list."
Aside from new orders, your tasting room (if you have one), and events where you pour your wines, your website is the best source of new e-mail addresses for your list. So, why aren't you getting more (or any) signups from your website?
This visually-excellent article from the ElasticPath blog has one answer: the signup form for your list isn't getting enough love on your website. And they point out the value of testing its location as well.
How do you grow your e-mail list? Share your expertise in a comment!