Gold Ridge Organic Farms: Olive Oil from Sonoma

Standing on a fold of land in southwest Sonoma County, looking out over farms and fields shading from spring green to summer’s gold, it’s hard to believe that the thrum of highway 101—the Bay Area’s main north-south freeway—is barely ten back-road miles away. San Francisco itself is just 50 miles south. But at Gold Ridge Organic Farms, the only sound is the afternoon breeze fresh off the Pacific Ocean, sighing through the 13,000 olive trees while hawks scan for unwary quails strutting and pecking through the grasses below.

Sonoma County is lucky this way. In this temperate Mediterranean climate, olive trees thrive, thanks to cool, wet but frost-free winters followed by long, dry, sunshiny summer days, and diurnal temperature swings that speed up ripening during the day, then slow it down with chilly nights.

Fortunate farming in Sonoma

Brooke Hazen of Gold Ridge Farms. Photo credit Dawn Heumann Photography

And while Sonoma County is lucky in its climate, this part of the county is even luckier in its soil. These olive trees are growing in Gold Ridge soil, a unique sandy loam that’s one of the best types of soil for grapes and fruit orchards in all of California. Brooke Hazen, founder and farmer of Gold Ridge Organic Farms, talks with reverence about the Gold Ridge soil supporting the olives, apples, and citrus trees growing on his family’s 88-acre property. Millions of years ago, this land was a seabed; the gold color that gives the soil its name comes from the land’s sandstone minerals. Olives, like grapes, hate wet feet; this well-draining soil keeps their roots from becoming waterlogged, yet it can also hold enough moisture, organic matter, and nutrients to support the trees throughout the typically rain-free months between May and October. (Because winter rain levels have fluctuated so drastically in recent years, the trees are minimally irrigated during the summer to ensure fruit quality and production levels.)

Hazen began his farm education at Green Gulch Farm in Muir Beach, an organic farm in nearby Marin County, affiliated with the San Francisco Zen Center. “I continued my own experiential lessons when I started my own organic, cool-season vegetable farm in 1996, only a couple of parcels from where I am now.” When he took over the family property in 2000, he knew he wanted to continue to honor the agricultural heritage of the area, which was famous for its Gravenstein apple orchards long before its Russian River vineyards became renowned.

Olive trees made sense for an organic orchard: They are low maintenance with a long natural life span and few pests or diseases, making them well suited for growing organically. And they produce a crop that can be transformed into a delicious, high-quality, high-value, shelf-stable product. “It is such a healthy, valuable, and venerated oil, the healthiest of all the oils we can consume,” says Hazen, a vegan with a deep interest in natural health and wellness.

Olives ready for milling. Photo credit Amy Sherman

Olive Varieties

In keeping with the Bay Area’ love affair with all things Italian, Hazen planted his first block of Italian varieties—predominantly Frantoio and Lecchino, with a small number of Maurino and Pendolino—in 2001, sourcing his young trees in one-gallon pots from McEvoy Ranch, an organic olive farm in nearly Petaluma. Over the next five years, he added another Italian block, this one focused on the Minerva olive, bred for cold hardiness after a killing frost decimated Tuscan olive orchards in 1984. Another swath was planted with Arbequina olives, along with five other Spanish varieties, including Empeltre, Leccin de Seville, Hojiblanca, Picual, and Manzanilla-- some to add complexity and aromatics to the final blend, others primarily as cross-pollinators. (Although olives are typically self-fertile and wind-pollinated, some cross-pollination is useful in increasing yields).

French olive varieties are typically grown as a table olive in the United States, if they’re grown at all, but the Picholine block, with additional plantings of Aglandau, Bouteillian, Solonenque, Grossane, and Cayon, has produced Gold Ridge Organic Farms’ most award-winning oil, winning gold and Best of Class 2023 in competitions.

How the Olive trees grow

Unlike the high-density plantings in the Central Valley, where olive scions are grafted to dwarf rootstocks and trellised like grapevines for maximum yield (with trees pulled out and replaced every fifteen years), Hazen’s trees grow the old-fashioned way, wide and bushy, eleven feet high with plenty of breathing room around each tree. They’re hedge-trimmed into what looks like a living green wall, with a tunnel of open space at the center of each tree to allow air and light to circulate (which helps stave off the fungal diseases that thrive in the damp and dark).

Milling Olives on site

Making olive oil at Gold Ridge Farms. Photo credit Amy Sherman

At first, Hazen milled his olives off site, selling the oil in bulk to other wholesalers. But, with the care he and his crew were lavishing on the trees—not to mention the miles walked daily up and down the rows, checking irrigation lines, keeping an eye out for the olive fruit fly, which can riddle a whole crop with its tiny eggs—he was finding it increasingly unsatisfying not to mill and bottle his own product. So, in 2012, a sleek shipment of Italian engineering arrived: a full set of Rapanelli milling equipment, from washer, crusher, and malaxer (an auger-driven mixing unit) to two-stage centrifuge. As director of operations Andrea Lederle describes it, these machines are the modern equivalent of “the donkey pulling the stone millwheels.” The process is swift and efficient, protecting the olives from heat and light that can degrade the oil, and extracting the oil with all its complexity and flavors intact. “I love making olive oils with complex, ingenious equipment. I feel I am carrying on centuries of tradition, but with a modern twist,” Hazen says. (Terms like “extra virgin” and “cold pressed” refer to older, more manual methods of extraction; with modern milling equipment, all the oil is extracted in one pass, with no need for heat or additional pressings.)

Starting in October, the mill has an increasingly busy schedule servicing over 200 custom-crush clients, from home growers with four or five trees to other small commercial growers. Unlike some other mills that combine all their clients’ olives in a “community press,” a crush run at Gold Ridge requires a minimum of only 50 pounds of olives, although a more typical run is anywhere from 500 to 2000 pounds. (Before you book an appointment, keep in mind that 50 pounds of olives—roughly the yield of a single prolific tree-- might give you, at most, a gallon of oil--“liquid gold” in more ways than one.)

Harvest Season

At Gold Ridge, the estate harvest begins in mid-November, with workers armed with pneumatic rakes shaking olives off the trees. Once harvested, the olives are brought to the mill within 24 hours. There, they’re cleaned, washed, crushed, kneaded, and finally spun—first to remove the solids, or pomace, then once again to separate the water from the oil. (These two by-products are returned to the orchard as mulch and irrigation.) Some oil is set aside as “olio nuovo,” the first of the season’s oil, thick with sediment, peppery and pungent with polyphenols, the bitter compounds that give olive oil both its back-of-the-throat bite and its celebrated antioxidant properties. Beloved by connoisseurs, this oil is sold on site only for the first few months after harvest; because it hasn’t been filtered, it has a shorter shelf life and degrades more quickly. The rest of the oil is sent through an accordion filter of tightly pleated cellulose, to capture any remaining water and sediment. Finally, the oil is pumped into stainless steel tanks, topped up with nitrogen gas to prevent oxidation. It’s bottled on demand and sold online and through a small selection of local stores.

Tasting Room

In 2021, Gold Ridge Organic Farms opened a tasting room adjacent to its production space and milling operation. In a large, airy building faced with chunks of golden stone echoing the color of the Gold Ridge soils, visitors can taste the farm’s four estate blends and three co-milled, whole-fruit citrus olive oils, including Meyer lemon, mandarin-kumquat and yuzu. Each of the four olive oils—Arbequina, Tuscan Blend, Minerva, and Picholine—has its own character, weight, and flavor profile.

Arbequina, buttery and smooth, with hints of sweet fennel, green banana, and stone fruit, is quintessentially Californian in its easy-going approach—no surprise, since Arbequina is the variety most widely grown in the state.

Prefer a little more bite? The Tuscan blend, primarily Frantoio and Leccino, has the classic, vivid green profile of a Tuscan-style oil, with notes of green grass and green apple, vigorous and lightly peppery.

Minerva, a blend of Minerva, Frantoio, and Maurino with a little Cersoula and Ladoeli, is something completely different: like bright, sun-flashed autumn day, with hints of toasted walnut and the mild tannic bite of papery walnut skin, green tea and white pepper—perfect for drizzling over a bistecca Florentine or grilled mushrooms.

Finally, the most intense, a local chefs’ favorite, comes the Picholine, tasting of bright, spicy greens like watercress, arugula, mustard and radish, a finishing oil for the boldest of flavors.

It takes hard work, long hours on the farm and a lot of technical know-how to produce a fine estate olive oil. But it takes a little poetry, too. “The most satisfying part of growing olives? How beautiful, elegant and timeless they are,” Hazen says. “I love that they have leaves year-round. I love how the trees ceaselessly grow in girth with their gnarly, nubby trunks and gracefully curving branches. I love the color of the leaves in the wind, and the sunset glow of the fruits at harvest time.”

Gold Ridge Organic Farms Olive Oil