The hot pink glow seen from space: Why these Ontario greenhouse lights still shine at night

The hot pink and canary-coloured hues glow so bright, astronauts can snap photos of them from space.

Fixed atop the largest concentration of greenhouses in North America, the multi-coloured lights have transformed both the night sky in a pocket of southwestern Ontario and the province’s multi-billion-dollar agriculture sector.

Over the last decade, vegetable and cannabis producers have installed thousands of lights inside greenhouses in Leamington and Kingsville, Ont., to grow plants year-round. But the glow emanating from Canada’s most southern region, sometimes seen from as far away as Michigan, has been the subject of both awe and concern, prompting local communities to adopt bylaws limiting the gleam of the greenhouses after dark.

“The technology came in so quick that being able to react and adapt to some of the perceived nuisances took some time,” says Richard Lee, executive director of the Ontario Greenhouse Vegetable Growers, which represents 170 members — most of which are in Essex County.

The rules have reduced the amount of light that spills into the sky. Still, the vibrant glow can be spotted at times from across the region — and even from the International Space Station, as it was in March.

“It's a lot of light,” says Starr Livingstone, the light pollution abatement officer for the Royal Astronomical Society of Canada’s Windsor chapter, adding that the glint affects their nearby observatory.