Tasting Dirt

"Radical transparency" about regenerative farming cuts through the greenwashing

Some wines grab your attention at first sip and refuse to let go. That happened to me last year as I was tasting a few pinot noir samples from Anderson Valley in California, trying to suss out a regional signature. They featured dark fruit flavors, rather like Russian River Valley but not as hefty; a middleweight, perhaps, compared to the lithesome, red-fruit driven pinots of the West Sonoma Coast; without the herbaceous root beer character of Sta. Rita Hills or the brash surfer ‘tude of the San Luis Obispo Coast. They were, in a word, delish.

And then I tasted DIRT. It was certainly in a class with the others, but it had an energy and tension that set it apart. This was a wine with something to say, and I wanted to listen.

To be fair, this wine wears its heart on its sleeve, or at least on its label. The essential information is there in modest type: DIRT Pinot Noir 2023, Mariah Vineyards, Mendocino Ridge. This is surrounded by an unusual amount of text in a ridiculously small typeface that made me want to check AARP benefits for eye care. The name stands for Directly Impacting Regenerative Transformation, the vineyard is certified regenerative by the Savory Institute’s Global Land to Market program, and the wine is lab tested to verify that it’s free of 500 potential chemical residues.

If you worry that eco-friendly claims by wineries are “greenwashing,” Michael Frey would love to talk to you.

“This wine is a statement that it is possible to produce radically transparent and nature-positive wine without compromise,” the label promised.

As much as I learned from the label, I wanted to know more, so I reached out to Michael Frey, who makes DIRT wines along with his wife, Nicole Dooling-Frey. Nicole’s parents, Dan and Vicki Dooling, planted Mariah Vineyards in 1979 with Zinfandel at 2400 feet elevation in what is now the Mendocino Ridge AVA. Over the years they sold most of their fruit, with Fetzer Vineyards during the Paul Dolan era a primary client, and for a time some wine was sold under the Mariah Vineyards label. Today, Mariah Vineyards has 30 acres under vine, with Chardonnay, Sauvignon Blanc, Pinot Noir and Primitivo in addition to Zin.

Frey, who hails from Switzerland, abandoned a hospitality career in his mid-30s to travel the world. He met Nicole in Peru and as their relationship grew decided to follow her home to California.

From left: The hyper-informative label of DIRT Pinot Noir; Michael Frey and Nicole Dooling-Frey with their son, Myles; Mariah Vineyards in the Mendocino Ridge AVA. Photos courtesy of DIRT Wines.

One day in 2018, Michael and Nicole had lunch with Paul Dolan, a friend of the Doolings since his days at Fetzer Vineyards. Dolan, who passed away in 2023, was a pioneer of sustainable and biodynamic viticulture in California, and at that time was helping set up the Regenerative Organic Alliance, an organization that would establish the Regenerative Organic Certification and promote regenerative agriculture.

Dolan “started speaking about regenerative viticulture, the possibility to bring back biodiversity, to sequester carbon, to create ecosystems rather than just extract from the land,” Michael told me. “It was so inspiring that we asked, ‘Why isn’t everyone farming this way?’”

After that lunch, the couple convinced Nicole’s parents to go all in on regenerative farming. They joined the Savory Institute’s program to measure and monitor biodiversity, soil health, water infiltration and other aspects of their land, an effort that is updated annually to measure and document improvements. They planted cover crop in the vineyard, including under the vines, to guard against erosion during the rainy season and cool the soil during drought. Sheep added biodiversity and nutrients while helping to maintain the cover crop. Following “Eco Agriculture” advocate John Kempf, they assessed sap samples from the vines against similar tests on the soil to identify nutrient deficiencies.

And then suddenly everyone was talking about regenerative viticulture.

So if you’ve been shaking your head while reading this, if you’re the type who looks at a sustainable or organic certification on a label and immediately thinks the winery is lying — because, well, Roundup — if you casually toss out the word “greenwashing” at wine tastings — then Michael Frey has something to show you. (Hint: it’s data.)

“And then we got to a point where regenerative viticulture became, in our opinion, a bit the buzzword,” Frey said.

“We saw social media posts about regenerative with drip-sprayed vines in the background, and we decided there’s a need for more transparency in the wine industry. And that’s how DIRT Wine was born.”

Radical transparency for Mariah Vineyards and DIRT Wine comes with an edge.

“I have strong opinions about a lot of things,” Michael said with great self-awareness. “I believe that every vineyard in California that is not working on climate resilience right now is really missing the boat. When I look back at my last seven years of involvement at Mariah, with the extremes we tackled, from heat waves to droughts to heavy rains — the future of wine is climate resilience. We have 100-percent ground cover, so no problem with erosion. When we have 110 degrees F¹ in the vineyard, the vineyard is cooling itself. It’s a flourishing ecosystem, with a lot of beneficial insects. We are off the grid, powered by solar. We have our own spring, so we don’t spray chemicals on the vineyard because they will get into our drinking water.”

This transparency, backed with data, is how Frey hopes to differentiate his wine from others.

“As a grower in an ocean of wine, it’s difficult to sell fruit,” he said. Being vocal and transparent about farming practices is a way to stand out from others who banter about “regenerative” without putting in the sweat equity.

In addition to the Pinot Noir, DIRT Wines offers a Sauvignon Blanc that features some of the same energetic tension as the Pinot, and a Chardonnay, which I haven’t tasted. The wines are in 398-gram bottles, among the lightest in California. These are the initial releases of Michael and Nicole’s deep dive into regenerative viticulture and transparency about their farming practices.

Mariah Vineyards still sells most of its fruit, and I suspect we’ll see the name on more bottlings from various wineries as the new farming practices show results. For now, at least, Michael and Nicole have put their own wines out there as a statement of what this type of farming and transparency can achieve.

The initial returns are in, and DIRT is a winner.

My transcription app compiled this summary of Michael Frey’s description of the “radical transparency” he practices with DIRT Wine and Mariah Vineyards:

DIRT Wine: What “Radical Transparency” Means in Practice

• Measured ecosystem outcomes

  • Partnered with the Savory Institute for Ecological Outcome Verification.

  • 10 short‑term and 3 long‑term monitoring sites, measured annually for biodiversity, soil health, and water infiltration to prove actual land improvement, not just claims.

• Plant and soil nutrition data

  • Regular sap analysis of vines to detect nutrient deficiencies (e.g., high iron in soil but low in plant).

  • Cross‑checked with soil tests to adjust farming and close the gap between soil supply and plant uptake.

• Chemical residues and additives

  • Wines are lab‑tested for 500+ chemical residues.

  • No additives except about 30 ppm sulfur; spontaneous fermentations, with Sauvignon Blanc going through natural malolactic.

• Farming and climate‑resilience metrics

  • Dry farmed (no irrigation) with roughly 80 inches of rain a year.

  • 100% ground cover, including under vine, to reduce erosion and cool soils during heat waves.

  • Vineyard is off‑grid, with its own spring for water and solar power, reinforcing the no‑synthetic‑input stance.

• Packaging footprint disclosed

  • Uses a 398-gram glass bottle, intentionally lighter than typical “premium” glass to cut carbon footprint.

• Outcome‑driven philosophy

  • Publicly frames all of this as an outcome‑based approach—tracking measurable results in soil, plants, and wine rather than relying on buzzwords like “regenerative” and “clean” without evidence.

1. He’s assimilating, even if he still has a Swiss accent.