Glassmaker Wine Co.

Reimagining California

Quick Facts

Location: Forestville, Sonoma County, California

Owner & winemaker: Jonathan Walton

Vineyard area: variable selection of vineyards in Sonoma, Lodi, Contra Costa, and Monterey counties

Vineyard management: practicing organics or biodynamics

Soils: wide range depending on vineyard – sand, loam, pebbles…

Main varietals: Zinfandel, Cabernet Sauvignon, Grenache; Grenache Blanc, Sauvignon, Roussanne

Winemaking: Spontaneous fermentation only, neutral barrels, no fining, no filtration, minimal sulfur additions.

Annual production (approx.): 500-800 cases


Fun Facts:

  • The winery was founded in 2015, taking Jonathan’s mother’s maiden name as its title
  • Jon’s reasons for making wine aptly sum up the ambivalent and communal nature of the natural wine world: “It’s something about loving hard work and getting dirty, then cleaning up and pretending to be fancy. It’s something about participating in a community of food and wine and friends and strangers that I love and admire.”
  • He’s working with various vineyards around California, trying to find the ones that “speak to him the loudest”, as he puts it. All of the vineyards are farmed organically or biodynamically, some by Jon himself.
  • Jon’s other big passion is photography, another way to capture nature’s beauty!

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Jonathan got his start in wine in the tasting rooms of the Salinas Valley “as a bored toddler eating oyster crackers off the floor while his father and friends casually imbibed glass after glass of the local red”, he recalls. From organic foods and fine cheese to the wines of France, Spain, and Italy, his curiosity in quality products led him to the soils of the vineyards of Sonoma, Marlborough, Lodi, CoCo. and Monterey. After a bit of blood and sweat at Brooklyn Oenology, Jonathan figured “it was time to put my money where my mouth was… and Glassmaker Wine Company is what happened!”

Founded in 2015 as a tribute to his mother’s maiden name and Jon’s family farming tradition (although that was more grains than grapes), the boutique winery allows Jon and his girlfriend Emily, who co-designes the labels, helps Jonathan around the winery and “generally helps out with farming when I beg her”, to reimagine California. “I’ve done this before; it might be the reason I keep living here. The geography and the communities of this large end of the continent are broad and strange, malleable and diverse. I loved wine when I left this place, and returning four years ago to farm the land has given me a new way to interpret both the past and future of these places. I am thankful yet aware that there is much more to feel, understand and imagine in this golden state.”

Jon himself farms a small plot in Healdsburg – the McGaraugh Vineyard in Alexander Valley, planted with Zinfandel and Petite Sirah. The rest of the wines come from a fluctuating selection of vineyards, as Jon is on the quest of trying to find the “terroirs that speak to me the loudest!” Their respectful management is a matter of course and includes organic or biodynamic practices and dry farming. This minimal input approach obviously extends to the cellar: the wines are all spontaneously fermented (both primary and malolactic fermentation), aged in old oak barrels, unfined and unfiltered, and made without any addition save for a tiny bit of sulfur. 




McGaraugh Vineyard Zinfandel

Jon on this wine: “This is a tiny angry vineyard I farm myself with absolute minimal inputs, on the southern end of the Alexander Valley. The Vineyard is a 2-acre northwest-facing bowl that is planted to about 80 percent of middle-aged Zinfandel vines. They are in conversion from double cordon to something more resembling bush trained, with the intention of allowing a more balanced canopy.”

Grape: Zinfandel with a touch of Petite Sirah

Vineyard: McGaraugh Vineyard, Alexander Valley, Northern Sonoma AVA. Dry-farmed by Jon himself

Personality: “The bowl shape causes the vineyard to ripen unevenly which translates into blazing raspberry acidity. A friendly, chill-able expression of Zinfandel, less ponderous more joyous!”

2020: “This year a couple things went against us, beyond the usual 2020 hat trick of two fires and a pandemic. There was a deer break-in during bud break that cut the yields in half. But the fruit that remained was true to form for this site, bright, raspberry, mouth-watering limpid,” Jon says. Destemmed, 6 months in old oak, no fining or filtration, 20 ppm of SO2 at bottling.

2019 was picked twice to balance the ripeness of different parcels and the tannic structure of the small amount of Petite Sirah. Destemmed and fermented in open-top vats, alternating between gentle pigeages and pump-overs every 48 hours till dryness. Aged 15 months in old oak before racking under nitrogen to bottling tank. Bottled without fining or filtration, 15 ppm total of SO2 received (5 ppm on its 1 year birthday and 10 before bottling).

Preston Vineyard Grenache Blanc Skin-ContactGlassmaker Grenache

Jon on this wine: “Grenache Blanc holds a special place in my heart and lineup as it was the first white wine I ever picked and made, from a small organic Chalk Hill vineyard that has since been lost to fire.”

Grape: Grenache Blanc

Vineyard: Preston Vineyard, Dry Creek Valley, Sonoma County

Making of: the grapes are hand-harvested and macerated on skins for 4 days. The wine then ferments and ages in neutral oak barrels (14 months with no battonage), then racked to tank to resettle for 6 weeks before bottling. Bottled without fining or filtration.

Personality: ripe caramelized fruit mingles with more light-headed notes of flowers, green almonds and some bright citrus lift. Super approachable and versatile kind of orange wine with mild tannins. And what a color! 

Hillside Vineyard Zinfandel

Jon on this wine: “In the hamlet of Talmage, where an impressive number of old vine vineyards thrive, I have the fortune to work with some really beautiful old vine dry-farmed fruit.”

Grape: Zinfandel 

Vineyard: Hillside Vineyard, Mendocino. Alluvial bench planted in the early 70s, dry-farmed.

Making of: The wine combines 3 different fermentations and two different ripeness picks. The first small portion of the grapes, about 20%, is a classic carbonic maceration, the next 20% is a structured whole cluster open-top fermentation, and the final 60% is a destemmed, very gentle, very cool open-top fermentation. Blended together and aged in old oak barrels for 15 months before racking under nitrogen to bottling tank. Bottled without fining or filtration, 20 ppm total of SO2 received (5 during elevage and 15 before bottling).

Personality: as Jon puts it, “a haunting wine that speaks of this calm, dry vineyard and translates the many of the redolent aromas I love from the inland Mendocino mountains!”

Mendocino Sauvignon Blanc

Jon on this wine: “The Hillside vineyard has two somewhat distinct portions: the old vine dry farmed zin – see above – which occupies the western higher portion of the vineyard, and the lower (by like 15 feet) gentle slope of trellised SB. Its large double cordons ripen slowly and retain blazing acid even in this quite hot site.

The 2021 wine is not vineyard-designated on the label because it has 20 percent of a new vineyard called Burnett, which is some really fun acid-driven stuff. This tiny 1-acre site is located in Bennett Valley, a cool inland valley next to Santa Rosa just west of the Russian River Valley. Even though it is further from the ocean than the Russian River Valley, it pulls in fog in a way that keeps it quite cool. It is a young-vine vineyard (planted around 2017) which I think complements the old vines on the other site. Not yet certified but has been farmed organically from its inception.”

Grape: Sauvignon Blanc

Vineyard: 2021 is 80% Hillside Vineyard (alluvial bench, dry-farmed) and 20% Burnett Vineyard (loam, organic)

Making of: The grapes were picked at the beginning of September and were partially destemmed, with 50% left as whole clusters. Sealed and left to macerate for 1 week before being foot crushed. They finished fermentation with gentle punch downs every other day till dryness. 6 months of elevage without disturbing. Bottled without fining or filtration, 13 ppm total of SO2 at bottling.

Personality: “such a laser of lemon pith, white rose, and even some red fruit. An intense purity. I like it with grilled veggies, lots of garlic, halloumi, mussels, clams, and grilled steak w olive oil and oregano!” goes the winemaker’s recommendation.

North Coast Orange

Jon on this wine: “Three different vineyards that kinda synergize to make a deep yet welcoming skin contact orange. The Hillside Sauvignon has large double cordons, ripens slowly, and retains blazing acid even in its exposed site, while the little Chenin portion is direct-pressed to mellow some of the SB tannins and add more honey, almond and apple notes to the finished wine.” 

Grapes: 65% Roussanne, 20% Sauvignon Blanc, 15% Chenin

Vineyard: Roussane is from Lake County; Chenin Blanc is an old vine dry-farmed site in Redwood Valley, Mendocino; SB comes from Hillside Vineyard, Mendocino. All certified organic (CCOF)

Making of: The Sauvignon grapes were picked at the beginning of September and were 50% destemmed, 50% left as whole cluster, sealed and left to macerate for 1 week before being foot crushed. They finished fermentation with gentle punch-downs every other day till dryness. Aged for 12 months in old oak barrels. The Roussanne received a week of whole cluster fermentation before it was pressed to finish off the skins, then aged for 12 months in old oak barrels. The Chenin was direct-pressed into old barrel where it spent 12 months in total. All indigenous yeast only, blended before bottling. Unfined, unfiltered, bottled with a small dose of SO2.

Personality: “Like sun low in the sky that might be rising, might be setting. These grapes are from Mendocino and Lake Counties. They combine aromas of cara cara red oranges and wet chaparral shrubs. It’s a wine for the shade of a redwood, or a sturdy old stoop,” says the winemaker. Notes of persimmon and acorn squash mingle with some light nuttiness and lemon oil. A more contemplative orange, both easy to have on its own or with richer tangy foods.


North Coast Red Blend

Jon on this zippy red-white coferment: “I was very happy to make a North Coast Red Blend as this style is close to my heart and bears more talking about. I’m very interested in expressing a macro picture of larger parts of California, and the North Coast AVA allows me to play with an imagined idea of fresh California wine. While the 3 sites blended have totally different unique terroirs, together I hope they say something about the potential of the region as a whole to provide happy approachable yet mysterious wines!”

Grapes: 26% Sémillon, 20% Roussanne, 30% Zinfandel, 24% Carignan

Vineyard: Roussane is from Lake County; Carignan is from old vine Deanda vineyard, Mendocino. Sémillon & Zinfandel come from a from a small knoll above the winery in Forestville.

Making of: The Semillon and Zin were picked and fermented together as whole clusters. The Roussanne was fermented on skins, pressed while still sweet and went dry in barrel, while the Carignan was a classic open-top whole cluster ferment. Blending was done to achieve the brightest moments from each grape! 6 months in barrel for all lots, with 20 ppm of sulfur before blending, and 5 ppm after blending. Bottled unfined and unfiltered.

Personality: as Jon says, “ocean spray and a rich texture from the white grapes, with high toned berry flavors and fine tannins from the reds. Some cofermentation, some elevage blending; the result brings light-lunch joy. The brightest moments!”

Cole Ranch Vineyard Cabernet Sauvignon

Jon on this wine: “I’ve found that the most compelling cab from California develops high up and closer to the ocean than you might think, whether that is Montebello in the Santa Cruz mountains, the Sonoma coast range or here in Mendocino….while technically not a coastal site, this vineyard does benefit from a complex interplay of cool sinks which place it in the coastal influence in my understanding. This unique aspect and air flow are what makes this the smallest AVA in the country, and one of the few California “monopoles”, as the Cole Ranch is the vineyard as well as the AVA.”
Grapes: Cabernet Sauvignon

Vineyard: Cole Ranch, Cole Ranch AVA, Ukiah, Mendocino. Coastal mountain terroir of alluvial soils, planted in the early 1970s. USDA organic farming

Making of: the grapes were destemmed and gently fermented with pump-overs and occasional punch-downs, to preserve the flower aromas. Pressed and then aged for 6 months in barrel. Unfined, unfiltered, 20 ppm at bottling.

Personality: “This wine is so pretty! Flowers, roses, cherries. It speaks to the coastal mountain terroir of alluvial soils, cold nights and cool air from the redwood canyons,” the winemaker says.

SunHawk Vineyard Grenache Red

“From the famed SunHawk Vineyard on the serpentine slopes above Hopland, this is a whole cluster partial carbonic Grenache that has a really electric combo of bright toots-fruit, baking spices and strong mountain tannin. Luck got me access to these vines and hopefully will keep me consulting in the vineyard,” Jon says.

Grape: 100% Grenache

Vineyard: SunHawk, Hopland, Mendocino county. Poor soils, south exposure. Biodynamic (Demeter-certified) farm with high biodiversity and polyculture, producing also olives and fruit.

Making of: spontaneously fermented as whole clusters, with gentle food-tread. 16 months in barrels, 15 ppm sulfur halfway through elevage. Bottled unfined, unfiltered.

Personality: an electric combo of bright toots-fruit, baking spices and strong mountain tannin. “A wine that will age but tastes too good to not have out into the world right now,” the winemaker says.