History
Part of the ground was an old Christmas tree farm. Pinot Noir went in on the Mount Eden selection in 1999, Sauvignon Blanc in 2000, Syrah in the same founding era. Ken and Abbey Swegles took over the farming in 2016, under the Skyline Viticulture banner and later Swegles' own Rhizos Viticulture; 2017 brought a Swan Pinot Noir block, grafted Gamay Noir, and the first of the trial whites. Cole Thomas founded Madson Wines in 2018; Ken Swegles and Abbey Chrystal are viticulturists and partners at the label, and Ascona anchors its range. The vineyard's own site now lists Joaquin Casanueva of Alesia Viticulture Services as manager. There is no estate winery and no tasting room; the property sells fruit and nothing else.
The Site
The vines sit high on the ridge on the Santa Clara County side: 13.6 acres, with producer figures for the elevation running 2,350 to 2,500 feet. Leo Steen calls it a sloping plateau; Big Basin gives the slope at 10 percent or less, facing south and southwest. The Pacific lies about fifteen miles west, sending overnight fog and steady ocean air, but the elevation holds the vines above the fog filling the valleys below, with the Big Basin watershed on one flank and Silicon Valley on the other. The soil is shallow sandy loam over Vaqueros sandstone, high in calcium carbonate, fast draining above base rock. Farming is organic in practice though not certified; Western Bluebird boxes stand through the rows for pest control, and Big Basin put one on its label.
Vines and Blocks
Pinot Noir is the core and spans four heritage selections: the original 1999 Mount Eden, Pommard 4, the Martini clone, and the 2017 Swan. Syrah is a field selection plus clone 470. Chardonnay is younger, Old Wente clones 72 and 76 from the mid 2010s. Aligoté began as a trial of 151 vines whose first crop, in 2021, came to about 36 pounds; another 250 vines followed, and Madson lists the selection as Ascona Doré. Arnot-Roberts describes its parcel, on the Christmas tree farm ground, as four and a half acres of 2000 Sauvignon Blanc with Gamay Noir clone 358 grafted in 2017, reported at the time as the appellation's only Gamay. The roster adds Cabernet Franc, Cabernet Sauvignon, Merlot, Chenin Blanc, Sangiovese and Negroamaro.
The Wines
Big Basin's Pinot Noir is whole cluster and native ferment, 18 months in French oak; the 2021 came in at 13 percent alcohol from a 146 case lot. Madson bottles Pinot Noir, Chardonnay and Aligoté from one of the first plantings to prove that variety viable in the region. Marbeso takes the Martini clone Pinot, also fully whole cluster. Arnot-Roberts bottles the Sauvignon Blanc and the Gamay, Leo Steen a Sauvignon Blanc and a Cabernet Franc bottled since the 2017 vintage, and the vineyard's client list adds Thomas Fogarty. The through line is the one the site sets: modest alcohol, firm acidity, and the mineral cut the calcareous sandstone gets credit for.