Is a Riesling Renaissance beginning in California? – Chapter 1 (Ryan Stirm)

Ryan Stirm’s “winery” inhabits the slab floor and metal siding walls of a repurposed warehouse on Santa Cruz’s west side, most recently used as a welding shop. Barrel racks now fill about half the floor, with room left for a tiny grove of stainless steel tanks, a crush pad during harvest, and a small lab year-round. “The space has advantages,” Stirm points out, not least that the rent is reasonable, and that “it is less tainted than apple sheds in Correlitos,” never having been used for anything organic. Metal and concrete harbor few pests or fungi and clean up easily – an advantage if the new use of the space is for wine.


The winery is home to Stirm’s eponymous Stirm Wine Company (, which made and marketed its first wines in 2013, when it was domiciled in Santa Barbara County, and to wines made for several custom crush projects, in some of which Stirm also has an ownership interest. The barrel racks are filled with mostly red wines – Zinfandel, zin co-fermented with a small amount of orange Muscat,Mourvèdre, Cabernet Pfeffer, and (in a tilt toward the mainstream) Pinot Noir. A single rosé is made from more or less everything (think Mission and Carignane in addition to the aforementioned varieties) that grows in the Enz vineyard, approximately 50 miles southeast of Santa Cruz in the Lime Kiln AVA. Whites, entirely tank raised, include a surprisingly appealing co-ferment of orange Muscat and palomino (!) from Enz, Grüener Veltliner from Rancho Arroyo Perdito in Santa Barbara, and several Rieslings: from old vines in the Wirz Vineyard in the La Cienega Valley AVA, a stone’s throw from Enz; from the Kick-On Ranch in Los Alamos, and from Luis Zabala’s rock-and-gravel strewn vineyard in Arroyo Seco. At least for 2016, the Zabala will go entirely into 375 or 500 ml cans for a project Stirm does with partners, but the other Rieslings are the core of Stirm’s brand. “We love Riesling,” Stirm explains, “it’s loaded with terpenes, transparent, dynamic and exciting.” Stirm is one of perhaps eight or ten young vintners, almost all newly minted, who are now rediscovering and reinventing California Riesling, searching out old vines when they can, buying fruit from growers who have planted Riesling when the cannot, and grafting or planting vines anew when all else fails.  With only a few exceptions, this cohort is focused on dry wines.  Watch this space for additional chapters of the Riesling renaissance in California.


Stirm, who grew up conventionally in an East Bay suburb, in a family with no special sensitivity to food or wine, developed an early interest in the out-of-doors, gardens, compost, farms and cooking. Initially tempted to choose his college based on the ranking of its wrestling team – he wrestled competitively in high school — he turned instead, in 2006, to viticulture, enology and soil science at California State Polytechnic University at San Luis Obispo. A senior-year internship at Saucelito Canyon Winery exposed him to dry farming. Some time in Australia’s Margaret River, a harvest with Martin Mittelbach at Weingut Tegernseerhof in the Wachau, and several years with Justin Willett at Tyler Winery in Lompoc cemented his interest in Riesling. Stirm thinks first and foremost about vines, farming and terroir, and currently manages 44.5 acres of vineyard across the northern Central Coast, including Enz.   He is a self-avowed “huge fan of dry farming [because] it saves money” and [because] it makes much better wines;” in 2017 33 of the 44.5 acres are both organic and dry-farmed.  He also likes old vines for their smaller berries and the greater grip they give to wines. Where Stirm controls the ways farming is done, he strives for relatively open canopies to discourage botrytis and develop skin tannins, which also darkens the skin color of berries, fostering deep flavors. In most of the vineyards from which he sources fruit, he tries to pick early. At Wirz in 2015 he picked Riesling at 21.1 Brix, almost a full degree less than the previous year, and 7-10 days earlier than other winemakers aiming to make dry wines, saying that he noticed “no loss of weight or fat or ripeness,” and that the result was “more in the [stylistic] direction I want to go in.” In the cellar, his approach is relatively straightforward, albeit with a few wrinkles. About 24 hours of skin contact is permitted before fermentation. Once pressed, the juice is moved to a closed stainless tank, wherein Stirm leaves a goodly amount of headspace. “Stainless steel does not breathe,” he observes, “but headspace ensures some contact with air.” Fermentations are spontaneous, and sulfur is avoided until later, while the tank’s temperature is controlled to between 17 and 23° C. Malolactic conversion is not interdicted and generally runs its course before the primary fermentation has ended. Sulfur (see above) is finally added after the later of malolactic conversion or primary fermentation is complete. The new wines remain on their full fermentation lees until May following the vintage, left entirely alone, without stirring. Because Stirm likes “the texture of wines bottled unfiltered,” he relies on the combination of full malolactic conversion and essentially complete dryness (less than 1 g/L of residual sugar) to make filtration unnecessary. (Worldwide, nearly all Riesling is filtered before bottling. Even makers who tolerate malolactic conversion say they would be unable to sleep nights if they did not sterile filter before bottling. Stirm is one exception.  So is Peter-Jakob Kühn in the Rheingau.  And Michael Malat in the Kremstal, but Malat also interdicts malolactic conversions.)


Ryan Stirm is an unusually curious winemaker. For the present at least, nearly every wine and vintage is an occasion for experimentation with some parameter of time, temperature or technique, while custom crush operations, grown just slightly, have the potential to finance grander experiments. He aspires to plant some Riesling in the Santa Cruz Mountains, perhaps in a vineyard he farms now for pinot noir near Glenwood, around 1000 feet above sea level. Longer term, he has his eyes on the Sierra Foothills. He says he might “take a gamble on higher elevation sites in Mariposa and Tuolumne counties,” to capitalize on “long, sunny, late season days” and “soils composed on granite and slate, trading warm southern exposures for altitude.” Or even farther north, where “pockets of granite and limestone” are found in the Trinity Alps.


Meanwhile, his 2015 Riesling from Wirz is delicious and impressive: Very pale straw.  Intense attack featuring lemon peel, pith and juice on an underlay of macerated herbs and stone fruit pits. Mint, tarragon and citrus throughout.  Smooth at mid-palate and resolutely dry and slightly grippy on the long, mineral-y finish. 


Stirm is also optimistic about the future of Riesling in California. Pointing to its history here, its late-to-ripen propensity, and the mini-wave of new producers featuring Riesling, he sees newfound enthusiasm for Riesling on the horizon.