Mary-Louise Parker as Nancy Botwin and Jennifer Jason Leigh on “Weeds.” (JORDIN ALTHAUS/SHOWTIME)

Which is why few were surprised when Showtime confirmed Wednesday what had been assumed since a mere 556,000 people bothered to watch the seventh-season finale’s first telecast: This summer’s eighth season of “Weeds” will be its last.

When “Weeds” debuted in August of 2005, it was about this mom — played by Mary-Louise Parker — who starts selling weed in her upper-middle-class California neighborhood to support her family after the unexpected death of her husband. Since then, The Widow Nancy has gotten around a lot, moving from city to city, done some pretty nasty stuff, including jail time, and been shipped off to rehab.

“‘Weeds’ has been a seminal series for Showtime and was key in establishing the network as a home for great original programming,” Showtime entertainment chief David Nevins said in Wednesday’s announcement. “It has had a groundbreaking run, and will be one of the longest-running comedies in the history of cable.

“It was very important to us that we bring the story of Nancy Botwin and her family to a satisfying conclusion for the devoted fans who have spent years following these characters.”