“Here we come a-wassailing among the leaves, so green.”

It’s the opening lyric of the “Wassail Song,” a familiar folk tune dating back to 12th-century England, and the concept for a new winter festival being offered from 2 to 5 p.m. Saturday at the Merryspring Nature Center in Camden.

The Winter Wassail celebration will feature nature-themed activities and an evening of poetry and song around a roaring bonfire.

The wassail outing celebrates winter solstice, which is Dec. 21. It is a nature-centered observance of the shortest day of the year.

Merryspring exists to promote awareness and proper stewardship of natural landscapes.

The 66-acre nonprofit park was founded in 1974 as a refuge that includes hiking trails, an arboretum of trees indigenous to Maine, herb and flower gardens and structures that serve as learning centers for the many educational programs offered there year-round.

Managing Director Toni Goodridge said access to the property is free. It is open to the public from sunrise to sunset, 365 days a year.

However, not everyone is aware of the center’s existence. “Every year, visitors who come here say, ‘I’ve lived here my whole life and I didn’t realize this was here,’ ” said Goodridge.

Merryspring Director Brett Willard is looking at ways to make the park more visible.

“One of my main focuses has been to expand Merryspring’s scope beyond its park borders by increasing the amount of education programs we offer, reaching out to new audiences with a diverse selection of programming, forging new partnerships with other conservation and environmental education organizations, schools and scouting groups in midcoast Maine and doing more community outreach through field trips and classroom visits,” he said.

Though the area affords a plethora of outdoor opportunities, the work is challenging for this small organization and its limited resources.

“I’ve had to learn to be creative,” said Willard.

The wassailing event serves as the perfect outlet to highlight the property’s varied landscape, including an apple orchard dating to the 1800s, because wassailing has become associated with hot mulled cider.

Wassailing is said to have originated in medieval times during harvest season, when people strolled about apple orchards singing, dancing and pronouncing blessings over the ground for a successful crop in the coming year. The word “wassailing” is derived from an Anglo-Saxon phrase meaning “to drink to one’s health.”

Saturday’s event will include workshops to make pine-cone birdhouses and evergreen crowns, children’s games, traditional wassail singing, roasting chestnuts over an open fire and, of course, cider. Local author Liza Gardner Walsh will be on hand to read from her new book, “Where Do Fairies Go When It Snows?”

Attendees are asked to dress warm for seasonal weather.