A high-tech greenhouse company supported by the City of Vancouver has gone bankrupt and one city councillor is wondering if taxpayers may be left on the hook.

Alterrus Systems Inc. leased a downtown parking lot at a cut rate price to run a so-called "vertical farm"

From the beginning, the plan announced by Alterrus and warmly endorsed by Mayor Gregor Robertson sounded utopic: a parking garage roof converted to greenhouses with crops laid out vertically to maximize production.

The company planned to grow 200 kilograms of fresh organic leafy green vegetables daily to sell direct to local restaurants and through the produce delivery service SPUD.ca.

The company scored a dirt-cheap rate on the space: $4,800 a month for the whole downtown rooftop.

VertiCrop

North America's first VertiCrop farm was built on the roof of a parkade in downtown Vancouver in November 2013. (Alterrus)

But just more that a year after it was launched, Alterrus's last financial filings in the U.S. place put the company's debts to 17 creditors at $3.4 million.

NPA Councillor George Affleck has raised questions about Alterrus's solvency in the past, and is now questioning the entire project.

"Was this the best deal we could get for that space?" he asked on Friday.

"I never got an answer to that, and now I'm worried about what the City of Vancouver and the taxpayers might be on the hook for."

The news comes the same week as the bankruptcy of Bixi, a company which was to play a part in the city's bike share program, which would be run by Alta Bicycle Share Inc. Affleck says both situations raise questions about due diligence at city hall.

In a written statement, the mayor argued the parking lot garden wasn't a flop, and also said Alterrus's troubles shouldn't be indicative of the performance of similar food ventures in the city. 

"It's disappointing to hear, but there are plenty of strong local food companies seeing success in Vancouver," Robertson said.

"Having Alterrus lease the space generated more revenue for the City than when it was a parking lot," he said. "I hope EasyPark will continue finding new and innovative ways to keep generating revenue from underused spaces like vacant parking lots."

With files from the CBC's Jason Proctor