All the musicians on stage at Rock the Garden last weekend seemed thrilled to be there, but none looked happier than Stef Alexander did offstage.

The Minneapolis rapper and sonic innovator better known as P.O.S. was spotted all over the festival both days. Simply there to hang out, he seemed happy to talk to anyone happy to see him. Which was pretty much everyone. In one particularly broad-smiled run-in Sunday, he had his angel-faced, devilish-grinned 2-year-old son, Lincoln, riding atop his shoulders.

"I couldn't even pick him up until about a month ago," Alexander said.

It was only 3½ months ago that Alexander endured what he called "the most horribly invasive, ridiculously painful surgery you can imagine," a kidney transplant he had waited almost two years to receive. The doctors had to go in through his abdomen, he said, "So just healing up from them having to cut into me has been a big part of it."

After more than a week at Hennepin County Medical Center, one month at home on bed rest and two more months of gradually active recovery — plus sometimes-daily doctor visits — Alexander, 32, believes he's finally able to do what he does best (besides maybe serving as his son's chariot).

"I love working," he said. "I love doing what I do and getting stuff done. And not being able to do that has really been frustrating."

He returns to the stage with his Doomtree crew Saturday at Bayfront Festival Park in Duluth on a now-annual hip-hop-meets-hippie-folk bill with Trampled by Turtles, an intrastate jaunt that also includes a warm-up gig Friday in Moorhead, Minn. He already delivered what he called a "tester" performance with Doomtree two weekends ago at the Green Line grand opening party in St. Paul, and he said it went well.

"As long as I'm doing it with Doomtree and have the gaps when the others are out front, then I think I'll be fine," he said. However, he added, "The P.O.S. shows are probably going to have to wait."

The transplant also put his usually hyperactive recording activity on hold, so you can imagine how much he's also raring to go on that front. He plans to release an EP of random P.O.S. material in the fall before starting on his next full-length album. He's also finishing his contributions to the next Doomtree record, which might — emphasize "might" — be done in time for the crew's annual Blowout concerts in December.

Other projects in the works: his ever-percolating collaboration with Astronautalis, Four Fists, which just announced a Sept. 7 gig in Madison, Wis.; the ever-perplexing Marijuana Deathsquads, which has mostly been on hold during his recovery; plus an upcoming recording session with fellow Deathsquad member and Gayngs/Poliça producer Ryan Olson featuring the likes of Har Mar Superstar, Lizzo and Jeremy "Spyder Baybie" Nutzman. He left it up to Olson to explain those latter plans (meaning the rest of us will probably hear about it the week of release).

Thankfully, his long-term diagnosis is good enough to support all these options and much more.

"I had somebody else's kidney dropped into me, and right now my body doesn't want it there and is fighting it," he explained. "But once that goes away, I should be able to do everything I did before."

Asked how he's staying positive in the interim, he said, "I looked at this whole thing the way I do a tour, where I don't know exactly where I'll be day to day but I know what I have to do. I embraced it as that: something I had to do."

That's one time we don't mind hearing a rapper brag about how good his work is.

Random mix

This weekend's Pride Festival in Loring Park features a diverse array of locals playing free sets: Mayda, Pennyroyal, Keri Noble, the Hollow Boys and Candy Shop on Saturday, followed by Toki Wright, Southside Desire, the Lioness, Bomba de Luz, Desdemona, Courtney Yasmineh and K. Raydio on Sunday (Noon-6 p.m.) … The Saloon in downtown Minneapolis has its own Pride Block Party on Sunday with Pop Rocks, Natalia Kills and Alex Newell (6 p.m., $20-$25). …

After Saturday's Bayfront show, Trampled by Turtles won't play another big show in Minnesota until their Festival Palomino on Sept. 20 at Canterbury Park, but they are teaming with the Electric Fetus for a private gig at the Cedar Cultural Center on July 10. Tickets came free at the Fetus with pre-orders of their album "Wild Animals," out July 15. … You can also catch TBT mandolinist Erik Berry doing a solo set Sunday at Duluth's Park Point Art Fair (1 p.m., free). …

Twang-happy singer-songwriter Jennifer Markey's annual tribute to her dad, the Honky Tonk Fest IV takes over Grumpy's Northeast on Saturday with Trailer Trash, Markey's group Second Cousins, violin maven Jillian Rae, Nordeast fixture Doug Otto, the Union Suits and Texan songwriter Leo Rondeau (2-9 p.m., $5). John Markey died of leukemia; the show benefits the Leukemia & Lymphoma Society. …

The Double + Good label hosts a showcase Friday at the Hexagon Bar with Self-Evident, Haunted Heads and Hardcore Crayons (10 p.m., free). … Drummers-gone-solo Dosh and S. Carey will represent the home team at the newly announced Aug. 8 lineup of the now two-day Skyline Music Festival at Target Field, also featuring Dosh's former employer Andrew Bird and New Pornographers. …

After her smoldering set at Rock the Garden last Saturday, Lizzo had this to say about her travel plans: "I'm just keeping my head above water and trying to enjoy it." She left town to play the Glastonbury Festival in England on Wednesday, returned for Summerfest in Milwaukee on Thursday, will be back in England for the Wireless Festivals July 4-5 and then has the Leeds and Reading festivals in August. Somebody is due for an awesome frequent-flier vacation at year's end.

chrisr@startribune.com •

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