Six Sigma Ranch

Six Sigma Ranch
13372 Spruce Grove Rd
Lower Lake, CA  95457

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Tasting Room Open Daily 11–4:30

Insider Tips

Special Notes

Private tours and barrel tastings by appointment, owner and winemaker on site, wine club discounts, picnic area


At Six Sigma Ranch, art is science—and perfecting the art of wine begins in the vineyards. Owner Kaj Ahlmann, a practiced mathematical statistician, applies the Six Sigma philosophy to the old-world art of winemaking in order to handcraft each bottle of Six Sigma Ranch wine to be as good as the next.  

The management practice of Six Sigma focuses on the pursuit of perfection. However, one must not be fooled into thinking that quality is all about control. Out of the 4,300 acres that make up Six Sigma Ranch, just 50 acres have been planted to grapes. By selecting only the very best sites, Six Sigma produces grapes that express the unique character of the Lower Lake County ranch.   

Strikingly picturesque, the balance of the acreage is dedicated as a nature preserve through a conservation easement donated to the Golden State Land Conservancy. When the Ahlmann family acquired the ranch in 2000, one of their top priorities was to create a sustainable ranch with vineyards nestled into the nature of Lake County. “Our love of nature is our driving force,” says Kaj. “We integrate the vineyards with native vegetation, making the grapevines a part of the natural landscape.”

This same attention to detail is carried through the entire winemaking process. “Six Sigma principles do not replace the creativity and art of winemaking. Instead, they provide a framework for measuring how close we are to our intended vision for each wine,” says Winemaker Matt Hughes. Matt joined Six Sigma Ranch as its first full-time winemaker in 2009 after spending 10 years in the industry perfecting his craft.

The Six Sigma Pinzgauer all-utility vehicle gives visitors a breathtaking high-altitude tour of a small portion of the ranch. The rugged ascent culminates at the Diamond Mine Vineyard, where Lake County diamonds glitter in the volcanic soil, not far from the spot Kaj’s beloved, rare Tempranillo gets its start.

At Six Sigma Ranch, meticulous attention to science and tradition produces wines always worth enjoying. 

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Six Sigma Ranch Label


Tasting Room: No

Complimentary Tastings: No

Tastings — By Appointment Only: No

Tours: No

Tours — By Appointment Only: No

Private Tours: No

VIP & Educational Experiences: No

Exceptional Views: No

Club Member Lounge: No

Restaurant / Deli: No

Food / Wine Pairings: No

Gift Shop: No

Wedding Facilities: No

Event Facilities: No

Corp. Meetings: No

Guest House on Premises: No

Lawn Games: No

Family Friendly: No

Pet Friendly: No

Family Owned and Operated: No

Wine Cave: No

Art/Architectural Interest: No

Sustainable Practices: No