Mosel in January

January = Brrr. I would probably choose to stay in Trier, where there are lots of warm cafes and museums that you can tuck into. The smaller Mosel towns where the wineries are tend to be shuttered. But I could still see doing an outing to Bernkastel from Trier - it's a handsome place. In Trier you can count on a good selection of Mosel wines in food establishments. Some wineries in the small towns also offer rooms and apartments in the off season, but you still might feel pretty isolated.

Some of the collectives where they sell the wine may be open. Germany doesn't have many "wineries" or wine estates, like in France, Italy or California... most of the grapes are grown on a small scale on leased public land. Provided that the paths are not covered in snow, ice or mud, you should be able to walk through the vineyards (as above, public access land), although obviously the vines will be bare. Don't expect a whole lot of activity, though. Most of the seasonal restaurants shut down for the winter.

When I was on the Mosel eight years ago, I intended to take in some wine tastings, but after the first one I realized that there was little point to it unless you planned on purchasing cases of wine from that winery. You can get as good an idea of the wines just by ordering several local wines off of the menu at a restaurant (I did that in Bernkastel). The only advantage to the wine tasting was that they gave small portions of the wines so you could "taste" a larger selection without drinking too much.

Looking at the website for Rademacher in Cochem, they indicate that there are wine tastings daily year round but only by appointment. I assume you could do a dropin tasting at the Weinstube, which is open Tu - Sat, April to early October). However, I was able to taste wines there as a drop-in in November. However, I just happened to catch the owner outside doing some maintenance, and he agreed to let me do a tasting - small glasses of four wines, two varieties from two different years.