Duck Walk Vineyards, 44535 Main Rd, Southold, NY 11971, US

In 2003, architectural project manager Carol Sullivan and Erich Moenius co-founded Gramercy Vineyards after discovering how ideal their 3.5 acres of sandy loam farm land in Mattituck was for growing merlot grapes. Located just south of Sound Avenue, the small plot is a "little oven" for growing exceptional merlot due to the way water and cold air tend to drain from the vines, according to noted winemaker Roman Roth. Mr. Roth, who is also the winemaker at Wolffer Estate Vineyards in Sagponack, has been helping the team at Gramercy produce three robust boutique wines: Rose, Estate Merlot and Reserve Estate Merlot. The wines are currently only available for purchase at The Tasting Room in Peconic. Each grape is hand-picked and sorted. "If you have one little berry that is damaged by a bird or from a bee sting it will get cleaned out," Mr. Roth writes on Gramercy's website. "It's like sanding the rough spots out so that you can work in a very rustic way, macerating all you can get from the grapes."