Sometimes an idea just sits waiting in your own back yard.

Scott Spencer is a Mount Desert Island native who has been living and working in the U.S. Southwest for the past half-decade. He still visits the island in the summer, and last year he was struck by the crowds that had drifted Down East.

“I said, `There’s so many people — somebody ought to do a show,”‘ Spencer said.

And that’s how the Down East Puffin Festival was born, a festival that will bring the likes of Jefferson Starship, Inner Circle, Andrew Tosh and the Beat Roots together for a daylong music festival in Blue Hill next month.

The Puffin Festival, however, is not Andy Rooney and the kids putting together a show in the garage.

Spencer is the president of Full Moon Productions, a full-service special events team with headquarters in New Mexico. His company has organized such events as Lollapalooza, The Solar Music Festival and the One World Music Festival, and has produced or promoted such acts as Blues Traveler, the Bodeans, Richie Havens, Ziggy Marley and Los Lobos.

“I decided to try to pull this together and do one show here instead of in the Southwest,” Spencer said.

The festival will run from 11 a.m. into the night July 22 at the Blue Hill Fair Grounds. Among the activities planned are wall climbing, skateboard runs, hot-air balloons, a food and craft village, and Maine’s largest drum circle. There will be speeches and demonstrations, some with a focus on environmental awareness, others sponsored by local and national nonprofit organizations such as the American Red Cross.

But the main focus of the day will be the music, which, Spencer said, should offer something for everyone.

“We’ve tried to include something for every age — from 14 to 50,” he said. “Jefferson Starship should appeal to the 32-50 age group, while the younger crowd will be attracted by Inner Circle.”

Jefferson Starship has its roots deep in the 1960s. It grew incrementally from the legendary Jefferson Airplane band, which was founded in 1965 by Paul Kantner and Marty Balin. Jefferson Airplane became the first San Franciso rock group to sign with a major label, and its first album, “Jefferson Airplane Takes Off,” was released in 1966.

Vocalist Grace Slick joined the Airplane in 1967, bringing with her the hits “Somebody to Love” and “White Rabbit” that helped define the “Summer of Love” and the new, psychedelic experience unalterably tied to San Francisco’s Haight-Ashbury district.

Jefferson Airplane disbanded in 1972, leaving in its wake a string of songs such as “It’s No Secret,” “My Best Friend,” “Come Back to Me,” and “Volunteers,” which was featured in the Oscar-winning film “Forrest Gump,” and the PBS documentary “Baseball.”

Band members drifted to other projects and other bands, often reconnecting over the years. In 1974, Kantner, Balin and Slick formed the nucleus of Jefferson Starship in its first incarnation, which also included bassist Pete Sears, drummer John Barbata and lead guitarist Craig Chaquico.

During the next two decades, membership in the band was fluid, with individual members departing for solo projects and sometimes rejoining the group. Starship’s breakthrough album, “Red Octopus,” came in 1975, and featured the hit single “Miracles.” The album took the group to the top of Billboard’s album chart four separate times that year.

The band now includes Airplane founders Kantner, Balin and bassist Jack Casady, and often features guest appearances by other Airplane alumni, including Slick and Airplane original lead vocalist Signe Anderson.

Their appearance this summer is part of a summer tour commemorating the 35th anniversary of Jefferson Airplane.

To many American listeners, Inner Circle is known mainly for two songs: “Bad Boys” — the gritty outlaw anthem that became the theme song for the television show “Cops” — and the upbeat dance number “Sweat (A LaLaLaLa Long).”

But the Jamaica-based quintet has made its name over a 25-year period that has seen it become one of the most popular and influential reggae groups around. It won the 1993 Grammy for best reggae album with the LP “Bad Boys” and followed that up with the 1994 album “Reggae Dancer,” which sold 7 million copies and earned the group another Grammy nomination.

Inner Circle’s brand of pop-oriented Jamaican beats has made the group one of the most accessible of the reggae genre, attracting a large crossover audience.

A charismatic reggae artist, Andrew Tosh bears an uncanny resemblance to his father, reggae legend Peter Tosh, both in appearance and performance. He began touring in 1988 and has completed many tours in the United States, Europe, Africa and South America since then. In 1989, Andrew Tosh and The Soul Syndicate Band earned a Grammy nomination for its album “Make Place for the Youth.”

Beat Roots, a local Hancock County band, has attracted a diverse and growing audience since it formed in 1995. The band’s self-described “world gypsy rock” blends a mix of various folk and world music with its roots of rock, jazz and funk.

The quartet offers original compositions countered by reworkings of traditional international folk tunes, and new renditions of select covers ranging from 1,000-year-old Celtic melodies to driving African percussion riffs and modern rock and roll rhythms.

The band has been a favorite at the Grand Auditorium in Ellsworth, at the WERU Full Circle Fair and at the Common Ground Fair, and also appeared at the Great Went with Phish. The band has toured extensively throughout the Northeast and has released three CDs on its own HUGE Records label.

Advance tickets at $15 went on sale last weekend in Bar Harbor at The Bridge, The Music Bar, Hemporium and Burwaldo’s; in Ellsworth, Stonington and Bangor at The Grasshopper Shop; in Blue Hill at the Blue Hill Food Co-op; and in Southwest Harbor at Island Music. Tickets also will be available at Bull Moose Record Stores. Tickets will be $20 the day of the event.