Lisa Robins is glad that more and more customers are coming into Vin Vino Wine in Palo Alto asking for natural wine -- sort of.

She's glad because any curiosity about wine, no matter the category, is a good thing. She's chagrined, however, when those customers can't quite explain what they mean by "natural" wine, or if they're attached to its most restrictive definition.

Natural wine has become a cultural phenomenon of sorts, propelled from the fringes of wine geekery into the mainstream. Its popularity has sparked a flurry of wine bar openings across the country, including locally, endless explainers and thought pieces (just this week, The New York Times asked, "Is Natural Wine Dead?") and heated debate about what natural wine actually means.

"To me, the idea of natural wine has become a little bit dogmatic and it imagines this world where either you make these zero intervention, very handmade wines, or you're an evil corporate entity, and what gets dismissed in that kind of dichotomy is every wine we sell," she said. "We like to place a much bigger emphasis on, how is that wine grown? How is it made and how much energy is in it when you taste it?"

Loosely defined, natural wine grapes are farmed organically with minimal intervention and no (or very few) additives -- though as Robins pointed out, there are numerous exceptions, from organic wines that are not certified as organic to small, thoughtful producers that add some sulfites to their wines to enable them to be shipped across the world.

Vin Vino Wine is one of several places to taste and explore the nuances of "natural" wine on the Peninsula. Read on for Robins and five other owners' picks for bottles they're excited about, from a cabernet sauvignon-petit sirah blend made in a garage in Yolo County to an orange Georgian wine made in large, handmade clay vessels called qvevri that are buried underground.

Lisa Robins, Vin Vino Wine, Palo Alto

2018 Siciliane Bianco 'Calaiancu,' Mortellito (90% grillo/10% catarratto), $26

Mortellito is a small, organic producer in the Southeast corner of Sicily. This wine is positively oceanic; it's briny, fresh and slightly savory. A small amount of skin contact gives it a deep golden hue, though I wouldn't classify it as an "orange" wine. The texture is quite fresh, but also has a hint of roundness. The nose gives up lush, ripe lemon with floral notes. I would drink it as an aperitif or with any light fish or shellfish dish. It's a wonderful, vibrant, offbeat white.

2018 Toscana Rosso 'Unlitro,' Ampeleia, $20

Ampeleia is a relatively young estate in Tuscany started by Elisabetta Foradori with a couple of partners. Initially, the idea was to plant Rhone varieties, but they've expanded their scope as they've learned what works best on the land. The farming is all organic, moving toward biodynamic. Unlitro is a 1-liter bottle of a mix of grapes grown at the lowest altitude on the estate. The primary grape variety is grenache, but there's also carignano, mourvedre, sangiovese and alicante bouchet in the mix. Aging is done all in concrete vats. The wine is a fresh, slightly herbal and vibrant pale red. The nose is all of the pretty aspects of grenache, fresh cherry/red berry with just a hint of Mediterranean herb. It's insanely quaffable, and the liter bottle makes the wine feel like it was grown to bring people together. I would pair it with grilled pork or hard cheese and charcuterie. The price point is also party-friendly!

437 California Ave., Palo Alto; vinvinowine.com

Kasim Syed, Salvaje, Palo Alto

2018 Pipeño Portezuelo, $45 (1-liter bottle)

I am really enjoying the Pipeño wines from Louis-Antoine Luyt out of Chile. The red and the white are equally tasty but I find myself going to the white more often. It's organically farmed, hand-picked and fermented on native yeast, like all the wines we pour. It is unfiltered and cloudy in the glass. It's fun to drink and has many tropical flavors going on, like lychee. It can go great with anything, from spicy Asian or Indian food, and is also tasty with pizza.

369 Lytton Ave., Palo Alto; drinksalvaje.com

Pavel Sirotin, Bevri, Palo Alto

Dakishvili Family Vineyard Cuvee, $80

This full-bodied amber dry wine is a blend of three Georgian endemic grape varieties: rkatsiteli, mtsvane and kisi, grown in the Dakishvili family estate vineyards of the village Kondoli, on the right bank of the Alazani river in the Kakheti region. This wine was fermented and matured in qvevri according to the UNESCO-recognized Georgian traditional wine production method. The wine offers complexity of dried white and yellow fruits complemented with roasted almonds and sweet spices.

Artevani, $80

Unique terroir red wine Artevani is made in the historic wine-growing Kakheti region from the organically grown saperavi grape variety. This full-bodied, dry red wine has a dense, dark garnet color, ripe red fruits and plums in the aroma, a palate of black cherries, plums, and earthy spices. Bold, complex structure yet smooth and well-balanced acid. It is a perfect choice for Georgian spices, dishes and meats.

530 Bryant St., Palo Alto; bevri.com

Zu Tarazi, BottleShop, Redwood City

It's hard to label a wine as natural wine since I don't believe there is a clear definition. This movement started in the '60s in Beaujolais with an approach of no additives in the wine. We think of natural wines as fruit that's sustainably farmed, no manipulating, little to no sulfites, a kind of hands-off approach.

There is a cool, youthful evolution of winemakers that's been going on in California, and one that I am particularly excited about is James Jelks of Florez Wines from Santa Cruz. He's been on his own since 2017 and is making some beautiful wines. One wine that I find to be fire is his recent California heritage field blend ($63). It's a blend of zinfandel, mourvedre, carignan, alicante bouschet, petite sirah and black muscat from a vineyard planted in the 1920s in Santa Clara Valley. While working for another winery he would pass this 0.6 acre on his way to work and decided to approach the vineyard owner to see if he can utilize this historic fruit. These are the stories that get us geeked about wine at BottleShop, and now we get to enjoy the finished product of this labor of love.

2627 Broadway St., Redwood City; bottleshoprw.com

Rocco Scordella, Vino Enoteca, Palo Alto

2016 Palazzo Tronconi 'Lauterie' syrah, $89

We decided in the last five months to add a few natural wines to our list and we see a great interest from guests. Since we opened we always had macerated (orange) wines (that are) usually loved by geeky sommeliers or wine people since they are not cheap and usually have a strong, nutty taste and a full body almost compared to a red wine.

(This wine) is organic and (undergoes) biodynamic cultivation, non-filtration or clarification over 15 months of aging in a used French tonneaux (an oak barrel). Dark ruby color with intense staining and deep tearing. On the nose you have an interesting balance of chocolate, vanilla, dark cherry and black pepper with a little hint of dried plums. A classic full-body syrah wine perfect for polpette (meatballs), game meats and grilled meats. I found very interesting how a wine with no controlled temperature, spontaneous fermentation and indigenous yeast could reach such a great balance.

700 Welch Road Suite 100, Palo Alto; vinaenoteca.com

Guillaume Bienaime, Zola, Palo Alto

2017 "Grandma's Garagiste" cabernet sauvignon and petite sirah blend, $70

I'm super excited to be serving and supporting an up-and-coming winemaker's truly garage wine. Juicy plum and blueberries come out of the glass, nicely balanced with black pepper and hints of licorice. We love it with our 30-day aged rib-eye (steak) that we've been serving as a special lately.

565 Bryant St., Palo Alto; zolapaloalto.com

Read an interview with the owner of Vineyard Gate Selections, a longtime natural wine shop in Millbrae, on our sister website, The Six Fifty.