In 1981, a Sonoma County vintner named Chip Lyeth came home from a trip through Bordeaux convinced of something the French had known for centuries: a great red wine doesn’t need to come from a single grape. He started blending Cabernet Sauvignon with its traditional partners on his own Sonoma estate, and in the process helped coin a word the whole California wine industry still uses — Meritage. Four decades later, the best California red blend wine coming out of Sonoma still follows two very different playbooks, and almost nobody puts them in the same article.
What Actually Makes a Wine a “Red Blend”
A red blend is a red wine deliberately made from more than one grape variety, built by a winemaker to achieve a balance, complexity, or character that no single grape delivers alone. That word “deliberately” is doing a lot of work — federal labeling law lets a wine labeled as a single varietal, like Cabernet Sauvignon, contain up to 25% of other grapes without disclosing it. So a fair amount of “single varietal” Sonoma wine is already quietly blended. Red blends are just the wines where the winemaker stops hiding it and puts the craft front and center.
That’s an important distinction, because “red blend” gets used carelessly. Grocery store shelves are full of inexpensive, sweetened California wines marketed under that name, and the category’s reputation has suffered for it. The blends coming out of Sonoma’s serious producers have almost nothing in common with those bottles beyond the label term.
Two Blending Traditions, Rarely Discussed Together
Sonoma County has two genuinely distinct red blend traditions, and they come from opposite instincts. One is built from scratch, grape by grape, in pursuit of a specific style. The other is inherited from vineyards planted more than a hundred years ago, where the blend was decided long before the current winemaker was born.
The Bordeaux Tradition: Building a Blend on Purpose
This is the tradition Chip Lyeth was chasing. It starts with Cabernet Sauvignon as the backbone — firm tannin, dark fruit, structure that can age. Around it, a winemaker works in supporting grapes the way a chef works in seasoning: Merlot softens the mid-palate and fills in fruit where Cabernet runs lean; Cabernet Franc adds lift and a savory, herbal edge; Petit Verdot, used in small percentages, deepens color and adds a spice note that’s disproportionate to how little of it goes in; Malbec contributes dark, plummy fruit. None of these grapes is trying to be the star. Each one is there to cover for what Cabernet doesn’t do on its own.
Gundlach Bundschu, California’s oldest continuously family-run winery, has been doing this since long before “Meritage” existed as a word. Founded in 1858 on the Rhinefarm estate where Sonoma Valley, Carneros, and Napa Valley meet, the winery’s Mountain Cuvée blends Merlot and Cabernet Sauvignon from hillside sites pushing up into the Mayacamas Mountains — fruit selected specifically to balance each other before a barrel is even filled.
In Alexander Valley, Aperture Cellars takes a more architectural approach. Winemaker Jesse Katz — who trained under some of Bordeaux and Napa’s most exacting producers before starting his own label — built the winery’s whole identity around Bordeaux varieties sourced from Alexander Valley and the cooler edges of Sonoma County, where a longer growing season gives the fruit time most warmer regions don’t allow. If you want to taste the backbone grape on its own before you try it folded into a blend, our guide to visiting Jordan Winery covers one of Alexander Valley’s benchmark single-varietal Cabernet Sauvignons — useful context for understanding what the blending grapes are actually working around.
The Field Blend Tradition: Sonoma’s “Mixed Blacks”
The second tradition isn’t designed at all, at least not by anyone currently working. In the late 1800s and early 1900s, Italian immigrant families planted Sonoma’s hillsides the way they’d farmed at home — not in single-varietal blocks, but with a dozen or more red grape varieties interplanted row by row, cuttings traded between neighbors, harvested and fermented together as one wine. Winemakers now call these vineyards “Mixed Blacks,” and a handful of them are still standing, still producing, well over a century later.
Zinfandel usually dominates a Mixed Blacks field blend, but it rarely stands alone. Petite Sirah adds deep color and a tannic backbone Zinfandel doesn’t have on its own. Carignane contributes brightness and acidity that keeps a high-alcohol Zinfandel from turning heavy. Alicante Bouschet — a teinturier grape with red-pigmented flesh, not just red skin — deepens color further and adds structure. The result tastes nothing like a modern, single-varietal Zinfandel: more savory, more textured, less about ripe fruit and more about the vineyard’s actual history.
Ridge Vineyards’ Lytton Springs bottling, from Dry Creek Valley, is one of the most famous expressions of this style — a field blend of Zinfandel, Petite Sirah, and Carignane grown on vines dating back generations. In downtown Sonoma, Bedrock Wine Co. pours from an even more extreme example: its home Bedrock Vineyard, planted in 1888, holds more than 20 interplanted varieties, co-fermented exactly as the original growers intended. The tasting room sits inside the historic General Joseph Hooker House on the Sonoma Plaza, by appointment, and the wines double as a fairly direct education in the county’s agricultural history.
A Third, Smaller Tradition: Rhône-Style Blends
A handful of Sonoma producers work from a third playbook entirely: the Rhône Valley, where Grenache, Syrah, and Mourvèdre (often shortened to “GSM”) get blended for a style that leans more toward red fruit, pepper, and dried herb than the darker, tannic profile of a Bordeaux blend. It’s a smaller category here than either of the two traditions above, but it’s not a novelty — Sonoma Valley’s Hamilton Family Wines makes a dedicated Rhône Red Blend, and Kenwood’s St. Francis Winery blends Bordeaux and Rhône varieties together in the same wine, treating the two traditions as ingredients rather than rival camps.
Ready to taste the difference for yourself? Sonoma’s red blend producers range from century-old Mixed Blacks vineyards to architect-designed Bordeaux estates. Browse the full winery directory to find a tasting room that matches the style you want to explore.
How a Winemaker Actually Balances a Blend
The two traditions don’t just use different grapes — they’re built in a fundamentally different order. A Bordeaux-style blend is assembled after the fact: each grape variety is picked, fermented, and aged separately, sometimes for a year or more, and only then does the winemaker sit down with dozens of trial combinations to decide the final percentages. That’s the “blending seminar” wineries like Aperture sometimes let visitors sit in on — watching a winemaker adjust a blend by five percentage points and taste the difference in real time is a genuinely useful way to understand why blending is a skill and not a shortcut.
A Mixed Blacks field blend skips that step entirely. Because the varieties grow interplanted in the same rows, they’re picked on the same day and co-fermented in the same tank — there’s no opportunity to adjust the ratio, because the vineyard already decided it decades ago. The winemaker’s job shifts from “design the blend” to “don’t get in its way.” Both approaches take real skill. They’re just aimed in opposite directions.
If you’re building a day around this, Dry Creek Valley and Alexander Valley are the two AVAs to anchor a trip on — one for old-vine field blends, the other for the Bordeaux tradition — and our guide to planning a Sonoma wine weekend lays out a structure for covering both without overdoing it.
What to Pair With a Sonoma Red Blend
The right pairing depends on which tradition is in the glass. A Bordeaux-style blend, with its firmer tannin and dark fruit, wants something with real fat to match it — a grilled tri-tip, braised short rib, or lamb shoulder will soften the tannin and let the fruit open up. A Mixed Blacks field blend behaves differently at the table: the brighter acidity from Carignane and the spice from Petite Sirah make it a natural match for tomato-driven food — a Sunday-style red sauce, a charcuterie board heavy on cured meats, or a wood-fired pizza. It’s not a coincidence that this pairing works so well; it’s close to what the Italian immigrant families who planted these vineyards would have been cooking at their own tables.
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Frequently Asked Questions
What is a red blend wine?
A red blend is a red wine deliberately made from two or more grape varieties, combined by the winemaker to build complexity or balance that a single grape can’t achieve alone. It’s different from an accidental blend — U.S. law allows up to 25% of other grapes in a “single varietal” wine without disclosure.
What grapes go into a Sonoma red blend?
It depends on the tradition. Bordeaux-style Sonoma blends lean on Cabernet Sauvignon, Merlot, Cabernet Franc, Petit Verdot, and Malbec. Heritage field blends, sometimes called “Mixed Blacks,” are usually Zinfandel-dominant with Petite Sirah, Carignane, and Alicante Bouschet interplanted in the same century-old vineyard rows.
What’s the difference between a Bordeaux blend and a field blend?
A Bordeaux blend is assembled deliberately — each grape is fermented separately, then blended to a precise ratio the winemaker chooses. A field blend is co-fermented straight from a vineyard where multiple varieties were planted together generations ago, so the “blend” was effectively decided by the original growers, not the current winemaker.
Are red blends considered less serious than single-varietal wines?
Some wine drinkers do treat blends as lesser, largely because inexpensive, sweetened “red blend” brands have dominated grocery shelves in recent years. But some of the world’s most respected reds — Bordeaux, Rhône blends, and Sonoma’s own Mixed Blacks field blends — have always been blends. The category’s reputation, not its quality, is what varies.
Where can I try red blend wines in Sonoma County?
Dry Creek Valley is the center of Sonoma’s old-vine field blend tradition, while Alexander Valley and Sonoma Valley anchor the Bordeaux-style side. Producers like Ridge Vineyards, Bedrock Wine Co., Gundlach Bundschu, and Aperture Cellars all pour tasting-room flights that put the two styles in direct contrast.