The Zin of Blending
Since I can’t taste your wine and so don’t know the profile of each individual component, it’s hard to give you “the right” answer. And I would hazard that there really is no right answer; it all depends on what you are trying to achieve in your final wine. Zinfandel is a fun grape to work with because it can be made in so many different styles, from heavy Port-style dessert wines to light, dry rosés. Similarly, Zinfandel exhibits extreme character differences depending on where and how it’s grown. Head-trained Zin from Amador County, California, for example, can be really rich and almost Port-like (even when made in a table wine style) whereas I find that “old vine” Zinfandel from the Russian River appellation of California is more of an elegant wine with fewer tannins and can be more food-friendly.
Which one is better? It’s impossible to say. It all depends on what it is that you like to drink. Sorry to put so much of the responsibility on you, but especially for home winemakers who aren’t marketing their wines to the mass populace (or even to a smaller, more local market), you are essentially making wine to please yourself.
That being said, however, I do think that at some level even we commercial winemakers do tend to make wines that we personally like to drink (or at least, let’s hope we do). To that end, there are some “classic” Zin blends out there that do seem to have risen to the fore as the more tasty and most logical of the bunch. I think Petite Sirah (also known as Durif) is an excellent blender for Zin. Traditionally a varietal popular in France, it was brought to California by nineteenth-century immigrants who settled in the Sierra foothills as well as in the Northern California wine country around Sonoma and Napa. Its inky blackness contributes to a denser, more purple color profile whereas its blackberry and brambleberry flavors lend dark fruit and berry characters to the more “red fruit” (currants, raspberries) aromas that Zinfandel can have. Petite Sirah also can really round out the mouthfeel of a Zinfandel and can contribute acidity and structure. Especially if you’ve got a lighter-bodied Zinfandel that lacks a little color and acid, Petit Sirah can be your best choice for a blender.
Don’t neglect the most traditional of all Zinfandel blending techniques – that of “field blending”. This practice started out sometimes not as a conscious practice but more of a happy (or haphazard) accident. As European immigrants (especially from Switzerland and Italy) planted Zinfandel and other Vitis vinifera varietal cuttings in California and other parts of the United States, they didn’t always know what they were putting in the ground. Lacking today’s genetic coding and plant identification tools, many vineyards ended up with a good percentage of “mystery grapes” intermixed with the intended grapevines. As early Californian winemakers discovered that these inter-planted vineyards usually made some pretty good wine due to the different grapes contributing something to the blend, they began to purposefully plant mixed grapes together. Back in the pre-Prohibition days, before Cabernet, Merlot and Chardonnay became popular in California, the most commonly inter-planted field blends consisted of Zinfandel, Alicante Bouchet, Carignane and Petit Sirah. “Field Blend” Zinfandels are still made today, with some from Amador, Sonoma and Napa counties coming from mixed old-vine (30-100 years old) Zinfandel vineyards that still reflect their nineteenth century roots.
So was your choice to add Merlot to your Zin a good one? No doubt there are many other blends you could explore in the future. However, if you feel that the Merlot/Zin blend was better as a sum than as its individual parts and especially if it tastes good and you enjoy the results, then you did the right thing.