A pedestrians passes by a “parklet,” created by extending existing sidewalk into a parking spot, on K Street NW in downtown Washington. (Amanda Voisard/For The Washington Post)

In the past week, carpenters screwed 10 banana-and-mustard-colored triangular planters, a bench and a table to a plywood platform taking up two parking spaces on K Street NW. Then they came back and touched up the paint and put up reflective safety posts. On Sunday, ferns and lavender are set to go in.

And on Tuesday, Washington’s newest park is to open to the public.

“I told my sister, ‘Hashtag: It-just-popped-up!’ ” said Randy Parz, one of the builders.

The District has started allowing people to take over parking spaces and turn them into year-round mini-parks. San Francisco helped spawn such spaces, dubbed “parklets.”

They’re part of a take-back-the-streets push to use urban asphalt for purposes other than, well, moving or parking cars. Think bike lanes and “road diets,” the practice of squeezing high-speed thoroughfares to a safer scale with medians or wider sidewalks.

This parklet on K Street NW in Washington is to open July 14. (Amanda Voisard/For The Washington Post)

Advocates say the parklets — parkitos? — are a potent way to bring a bit of warmth to utilitarian city streets.

Some bothersome details are still being hashed out as the District ramps up its program, including who will eventually cover the thousands of dollars in annual parking meter fees that are still required by law, even when the only things parked in the spaces are people.

Ryan Fleming, who runs the coffee and cocktail shop Slipstream near Logan Circle, was sold on the idea by the scene along San Francisco’s Valencia Street. The rustic wooden tables in reclaimed parking spaces there helped make the whole expanse — sidewalk and roadway — feel like a public park, “not just a place to go from A to B,” said Fleming, who is hoping to replicate the idea on 14th Street NW. “Instead of being like a highway, it brought life to the whole sidewalk.”

But skeptics see a gratuitous slap at car culture.

“It’s a waste of space. I really do believe so,” said Terence Pendergrass, a records assistant at an international elections monitoring group with offices near the new K Street micro-park. “Try to find parking down here this time of day. I think that’s absolutely ludicrous.”

Sam Zimbabwe, an associate director at the District’s Department of Transportation, said the city is treating its first batch of parklets as something of a pilot. There have been “growing pains,” he said, noting that plans for parklets in Georgetown were delayed over a city requirement that a professional engineer sign off on the soundness of the facilities, which need platforms to be accessible for people with disabilities. That sign-off requirement was eventually loosened. As for meter fees, the city is ponying up for a couple of years but has not found a long-term solution.

Concerns about the loss of precious parking spots are premature, Zimbabwe said.

“We’re not at the point yet where we have an overpopulation of these things or an over-demand that starts to eat at the parking supply,” he said. “If we get 10 applications on a street and every other business in the area rises up against it, we’ll have to consider those trade-offs.”

The young designers who came up with the concept for the K Street “parKIT” — as in “tool kit for DC parklets” — are aiming to lure all comers, skeptics included, with weekly programming and a barrage of good cheer. “It’s like a perfect opportunity for them to go outside their building and have lunch and have a moment in their day to think about things other than work,” said designer Claire Kang.

The site is at 2020 K St. NW in front of the offices of the global architecture firm Gensler, where Kang and her design partner, Laura Carey, won an internal competition for their park idea.

Along with placing the plants on Sunday, volunteers from Gensler also will be laying yellow triangles nearby with chalk spray, “almost like dispersing the parklet onto the sidewalk,” Kang said. Although the city allows parklets year-round, plans are to dismantle the K Street facility at the end of October, given concerns about foul weather and the movement of snow plows.

In addition to the fixed planters that help to set the boundaries of the space and provide a required safety buffer between visitors and passing cars, there are a half-dozen movable “modules” to use as seats or tables. The plan is to shift the pieces around monthly, guided by suggestions from visitors, Kang said.

The Golden Triangle Business Improvement District put up the $15,000 construction budget and will co-host Tuesday lunchtime civic sessions there under the banner “Making the City.” One week, a 3-D printer will churn out a replica of the park. Another week, passersby will be invited to doodle their own future parklet designs on the backs of business cards or on Post-it pads.

“It’s an attempt to create a different kind of energy on K Street,” said Leona Agouridis, executive director of the Golden Triangle business group, which has led a number of street and park upgrades in downtown Washington. “All of us are just running. Especially in the central business district, you’re running from one place to another. It’s really just kind of nice to stop for a moment and engage with a public space. Maybe I’m just a public-space wonk.”

Of course, in the public square, opinions are plentiful.

“This is a place of work. Why would you put a park here in all this traffic?” said Vincent Thompson, a lifelong D.C. resident who imagined children becoming agitated as cars speed past in the traffic lane.

But many were ready to embrace the reformatted space.

“It will bring a little touch of feng shui. We need this type of thing in cities, psychologically,” said Eliza Moody, a health-care educator who was working nearby.

Others were thinking primarily about their feet.

“We don’t have any chairs. Those are for the customers,” said Reynold Flores, referring to his nearby workplace, the Prime Rib steakhouse, where he is a valet. “After we park cars, we’re going to sit down.”