SOUTH PORTLAND – Marianne Russo’s tea room, Nellie’s Tea & Gifts, is a little out of the way, located at 5 Industry Drive in South Portland, but it’s on the map for the national Tea Across America campaign.

Launched at the inaugural meeting of the U.S. League of Tea Growers at the World Tea East convention this past October in Atlanta, Tea Across America aims to place one tea plant (scientific name: Camellia sinensis) in every state to help promote the fact that tea is increasingly a domestic product.

The brainchild of Jason McDonald, who last year founded FiLoLi Tea Farm in Brookhaven, Miss., and Elyse Petersen, founder of Hawaii-based Tealet, Tea Across America is promoting the groundbreaking of new tea fields in Alabama, Mississippi and New York, as well as the belief that tea can be grown in all 50 states.

“Camellia sinensis may not be ideal in every climate of the country, but the purpose of this campaign is to bring awareness to U.S.-grown tea,” said Petersen, on the Tea Across America blog on her company website.

Tea typically is not grown in Maine, and could only be cultivated in a greenhouse. According to Nigel Melican of Teacraft Ltd., “tea is happy” between 55 and 90 degrees Fahrenheit and will go dormant at temperatures below 50 degrees Fahrenheit.

“Although our Maine climate is too cold to nurture a tea crop of any size in our outdoor environment, we jumped at the opportunity to host Maine’s plant and help raise awareness about the movement toward making U.S.-grown tea a reality,” said Russo. “It will be exciting to see over the next 10 years or so what the quality of the tea produced will be like.”

A former nurse at the University of Southern Maine, Russo founded Nellie’s a decade ago, to re-cultivate happy memories of her childhood.

“My dad and his family were from England and so tea was a part of my life growing up, and my grandmother made all these goodies to go with it,” said Russo. “I thought that was true for everybody until I discovered it wasn’t. Still, I always had in the back of my mind all my life, wouldn’t it be nice to have a little tea room?”

That dream became a reality after Russo attended a “tea school” in Western Connecticut, hosted by the founder and editor of Tea Magazine.

“I came away thinking, I have to do it,” said Russo.

She opened up in a corner of Pot de Fleur, in shared space with an existing florist and art gallery then located in a Victorian building at 265 Main St. in Biddeford. But when the landlord lost the building five years ago, Russo began the hunt for a rent she could afford closer to her Scarborough home. That led to the Industry Drive space, which, adorned with tea sets and elegant decorations, can hardly be recognized as a portion of the building belonging to her plumber.

“Luckily, I developed a following in Biddeford. And then, having worked at USM, I am known to many people this way as well,” said Russo, who retired from her nursing job four years ago.

Despite being off the beaten path, Russo has a regular clientele. A member of the U.S. Tea Association and the Specialty Tea Institute, Russo is one of a select group of Certified Tea Specialists in the world. While not a formal tearoom, because that would require her shop to be run as a restaurant, Russo does hold licenses to conduct tea service and special tasting events, as well as off-site catered tea parties.

“We can do it any way people want, although my preference is not to do it too snooty, such as worrying about how one should hold the cup,” says Russo, with a laugh.

Although Russo has had a go growing and making tea herself – “It’s not an easy thing to do,” she says – she doubts cultivating the State of Maine plant will be a possibility. For one thing, it’s only about two years old, whole tea plants don’t hit maturity until they are four years old. Even then, tea is only harvested from the newest leaves and buds on a plant. It then takes about an ounce of dried leaves to make 12 teaspoons of tea.

“It’s hard to get enough to do that with from one plant,” said Russo. “I think the main thing people need to know that maybe people don’t realize is that every kind of tea, green or black, comes from this type of plant. There are many different varietals, but it’s all from this type of plant.”

There are 49 other states she is informally “competing” against. It’s not a contest, of course, but growers in all 50 states want their plant to be the best, or, at least, no one wants their plant to be the first to die.

“We’ll be posting on the Facebook page for Tea Across America from time to time, to let the whole country know how our plant is doing,” she said.

Marianne Russo, owner of Nellie’s Tea and Gifts, poses in her shop at 5 Industry Drive in South Portland with the State of Maine Tea Plant, hosted at her shop as part of the Tea Across America campaign, in which a plant has been sent to a shop in every state to promote domestically grown tea.