Correction: An earlier version of this article included an incorrect time reference for a December ruling by the Prince George’s County Historic Preservation Commission and incorrectly said that the commission heard arguments in an appeal of that decision this week. The arguments were heard by the Office of the Zoning Hearing Examiner. This version of the article has been corrected.

As motorists drive north on Route 1 in Prince George’s County, a dilapidated greenhouse with boarded-up windows is one of the first things they see as they travel into the Arts District of Hyattsville — a city determined to attract economic development.

City officials eager to revitalize the corridor targeted the old building, with its aging green awning and overgrown weeds, in a venture to refurbish it as a home for a nonprofit arts group and as the new location for one of the region’s hottest restaurants, Pizzeria Paradiso. Officials hope to do so with the help of $90,000 in federal funds designated for fixing up aging properties.

“It’s just an atrocity,” said Barbara Johnson, executive director of ArtWorks Now, the group behind the project. “This has been the lagging piece, and the city has been working to try to find someone to purchase the property . . . and show purpose for its use.”

But there’s no guarantee the project will be finished. The renovation has been slowed by a weeks-long disagreement between the Prince George’s Historic Preservation Commission and ArtWorks Now over whether the building should be designated as historic. And because the $1.8 million project has taken so long, county officials are working quickly to restructure the terms of the federal block grant that is helping fund the renovation — the funds must be spent by May 2, or the county will lose the money.

Those associated with the project are optimistic that the money will be awarded and the project completed. “We’re excited about being part of the neighborhood,” said pizzeria owner and chef Ruth Gresser. “Any company in the region should look into Prince George’s County for business.”

Part of the reason for the scramble is that U.S. Department of Housing and Urban Development sets strict timelines for using the grant money, known as Community Development Block Grants, and many Prince George’s recipients — including the city of Hyattsville — are taking too long to complete their projects.

Last year, Community Development Block Grants were awarded to local nonprofits and municipalities to finance projects throughout Prince George’s, but some have struggled to spend the money or had funds left over, or the projects fell apart.

The reimbursable grants are designed to improve blighted communities where a majority of families are of low to moderate income. Hyattsville’s median household income is about $56,534; the county’s hovers around $73,000. About 10 percent of Hyattsville’s approximately 17,000 residents live below the poverty level, according to the U.S. Census Bureau.

So now, County Housing and Community Development staffers are in the midst of a last-ditch effort to recover any unused or leftover money from awardees and reallocate it into a loan program to help families rehabilitate their homes. Federal approval of the plan is pending.

“We’ve been in a mode whereby we’re always trying to save CDBG money that should’ve been spent,” said Eric Brown, the department’s director. “It has consumed the staff.”

Caught in the sweep were the funds awarded to Hyattsville last winter to refurbish the flower shop and greenhouse on Route 1 to accommodate ArtWorks Now’s after-school programs, gallery space and offices, plus the restaurant.

Officials had done quite a bit of work on the property. Designs were drawn, purchases were made, and deals were struck. But the spending was delayed by a decision by the preservation commission in December to designate the Rhode Island Avenue building a historic site.

Built in 1951, the structure was designed for the successful Marché family of florists and sold in 2001, according to the commission. The classification as historic sets strict construction conditions that can significantly increase costs, Johnson said. She is appealing the decision, and the county’s Office of the Zoning Hearing Examiner heard arguments this week.

But the time lost coincided with the growing pressure Brown and his department was feeling from the federal agency to reallocate the grant money. Brown’s department asked for the $90,000 grant back, but the County Council interceded, saying ArtWorks had already invested $50,000 and was well on its way to spending the rest. “We were able to save it,” said County Council member William A. Campos (D-Hyattsville).

But that gives the nonprofit about 10 business days to spend the remaining funds and turn in receipts to Prince George’s housing officials.

Meanwhile, Brown and his staff are working to secure HUD’s approval for reallocating the money.

“I haven’t seen any person in the community that isn’t fully supportive,” said Johnson, adding that the project has also received funding from the state. “It is moving forward, and it’s unstoppable. It’s just a matter of time.”