A Gatineau, Que., medical marijuana company is continuing its rapid expansion ahead of the planned legalization of cannabis by building a new one-million-square-foot greenhouse near the Ottawa River.

Hydropothecary, founded in 2013 in Masson-Angers in east Gatineau, has around 100 employees working in 50,000 square feet of production space to churn out 3,600 kilograms of dried cannabis per year.

In October it broke ground on a new $25-million, 250,000-square-foot greenhouse.

Tuesday it announced it had bought a package of land next to its property on chemin de la Rive and would be using it for another one-million-square-foot greenhouse at a cost of $80 million.

The smaller new greenhouse is expected to be ready by July 2018, with plans to open the larger greenhouse in December 2018.

"Once legalization and the adult-use recreational market become a reality, Hydropothecary will be ready," said CEO and co-founder Sebastien St-Louis in a news release.

When all is said and done Hydropothecary said it will be able to produce 108,000 kilograms of dried cannabis per year, 30 times more than it can currently grow.

It said the expansion will create another 200 jobs in the greenhouses, with another 100 construction jobs while it's being built.