Etsuo Asano is Japan’s undisputed rock star of specialty vegetable farming.

The 65-year-old Chiba native, who’s been tilling the same land that’s been in his family for over 100 years since he was 17, supplies vegetables to some of Tokyo’s top eateries, such as Ristorante Hiro Centro in Marunouchi and the Michelin 3-star rated Quintessence in Shirokanedai. His chicory radicchio is said to rival the best produced in Europe, and his rucola (or rocket) is now legendary among Tokyo’s gourmet elite. Today, more than 130 restaurants across Japan buy his produce.

On the day I meet him he wears a dark brown velour, collared shirt tucked smartly into faded blue jeans that bear witness to his earth-intensive trade. He also dons an army-green conductor’s hat with a rhinestone encrusted patch of the word “Fresh.” Though small in stature, broad-chested Asano appears as if he could move a horse. His deeply tanned hands move quickly, confidently.

He ushers me into the cramped test kitchen he keeps on the farm. This is the “lab,” he explains, where chefs can experiment with his latest vegetable creations on the spot. The walls are plastered with photographs of Asano and the many famous food personalities who have made the pilgrimage to his Chiba Prefecture farm, affectionately known as “Chef’s Garden Farm.”

Several photos are of the renowned French chef, Pierre Gagnaire, whose eponymous Tokyo restaurant recently shuttered its doors. Gagnaire, known for his own rock-star flair in the kitchen, is exactly the sort of chef Asano likes to partner with. Both are visionaries, and both enjoy pushing boundaries and entering new frontiers. Glancing back at the tiny confines of the kitchen, one wonders what culinary delights have been cooked up within these walls.

There are also countless photos of Japanese celebrities, both major and minor, who come to his farm to “touch the earth,” as he says. These are his groupies. “They come to escape the enormous stress of their busy lives,” he explains, adding with a chuckle, “Sometimes they even help out.”

Behind every rock star is an able and trusted manager. In Asano’s case, that’s Kentaro Uneta. The two met 15 years ago when Uneta was in charge of sourcing produce for a high-end fruit-and-vegetable chain shop.

“Asano is a great talker,” said Uneta, “and I was drawn to him for his passion for farming.” Soon, Uneta began dropping by the farm even if he had no business to conduct, the two often talking late into the night. A fast friendship and partnership was born.

The pair’s first success was rucola. “Asano was seeking ideas for a new vegetable to grow,” Uneta explains, “and I suggested rucola.” Up for the challenge, Asano obtained seeds himself and proceeded to scatter them all over his greenhouse, tending to the soil in his usual manner. “The result was amazing,” said Uneta, “but at that time we didn’t really know what to do with a greenhouse full of rucola, no matter how good it was.”

Uneta knew he had something special, and now he just needed to find the right audience. He had an image that Aoyama was a swanky area, so he bought a restaurant guidebook and proceeded to knock on the doors of restaurants in the upscale Tokyo neighborhood. Rucola was already being cultivated in Japan, but nothing came close to Asano’s, Uneta told me.

“The first place I walked into was a restaurant run by Yoshimi Hidaka, who now heads Ristorante Acqua Pazza in Hiroo,” he explains. “After just a few bites, Hidaka immediately said ‘leave all the rucola you brought in today.’ ” The rest is history; their rucola was an overnight success.

The pair began to expand into other areas, such as exotic carrots, radishes and radicchios, and word began to spread in Tokyo food circles. Soon, chefs were knocking at Uneta’s door. Magazine and newspaper articles followed. Asano’s fame grew.

Now, when deciding which vegetables to grow, Asano considers not only the needs of chefs but also the experience of restaurant-goers. “People get dressed up for a nice dinner out, and they expect a little more,” he says, adding, “and it’s my job to give them a bit of drama with my vegetables.”

But what’s the secret to Asano’s farming? If you ask him, don’t expect a straight answer and be prepared to be fed — well fed. The always-smiling and jovial Asano would rather offer samples of his brightly colored and tasty vegetables than discuss soils or farming techniques.

He first offers a plate of raw carrots — of no less than five colors, including black, yellow and white. Next, he serves up a cheese-topped vegetable casserole crammed full of iridescent radishes and still more carrots. Finally, after yet another vegetable dish, we head outside.

Touring the fields of Asano’s farm is like entering an artist’s studio. But the shyness of a reclusive artist is not here. He rips from the ground specimen after specimen, eager to show his masterpieces. His face beams in the late-evening sun as he offers samples cut with his ever-present pocketknife. One small radish he slices in half reveals a purple and yellow core. Its taste is sweet and of minerals.

It’s hard to keep up with the sprightly farmer, who moves from crop to crop with the speed and agility of someone much younger. We come to one of his latest efforts, an enormous alien-looking plant with a rather misleading name, “petit vert,” or “little green.” The plant, a hybrid of Brussels sprouts and kale developed in Niigata Prefecture, has little growths on its 30-cm long stems resembling small cabbage heads. These are the edible bits. I try one. It tastes like sweet cabbage.

We end our tour in his daikon radish patch. He pulls from the earth a deep purple 35-cm specimen and hands it to me. I struggle to hold on to the mountain of “samples” he keeps generously offering.

A light drizzle sends us back into the cozy comfort of his test kitchen, where he seizes on the opportunity to offer even more vegetables. This time it’s endives and Castelfranco radicchio, an edible flower resembling a head of lettuce with red and purple speckles. Both are delicious.

I try one final time to glean a few secrets from Asano on his farming. He tells me a story instead. When a Chiba Prefectural Agriculture Experiment Station conducted a test of his soil, the report came back showing it was nutrient poor. “I could not have been more pleased,” says Asano surprisingly. “That means I haven’t added anything unnecessary.” Herein lies at least one secret to his craft.

While most farmers worry about feeding their soil with nutrients (which often means chemical fertilizers), Asano focuses on achieving a “mineral balance,” as he explains it. To do this, he uses crushed oyster shells and a sprinkling of deep-sea water from off the coast of Mie Prefecture, which he keeps at a constant 3 degrees Celsius (the same temperature of the water when it was collected). The shells and the seawater are both rich in minerals, especially sodium, magnesium and calcium, giving the soil what he sees as a “primal quality.”

“Life came from the sea,” he tells me, “so what better place to get the basic ingredients for my soil.” He also does his best to leave the vegetables alone, in what he likes to call “untended farming.”

And while his approach means some vegetables are smaller in size than those grown in nutrient-rich soils, the difference is in the taste. Everything I sampled during my memorable visit to Asano’s farm was remarkable for its rich, almost sweet taste.

Whatever he is doing is obviously working.