Prime Minister Justin Trudeau believes Canadians should be allowed to grow their own cannabis, but he must now decide whether he wants to enter into a fight with the Senate to make it happen across the country.

Bill C-45, which was adopted by the Senate with 46 amendments on Thursday, allows adult Canadians to grow up to four plants of cannabis in their homes to meet their personal needs.

However, Manitoba and Quebec have decided to prohibit home cultivation as part of their respective plans to legislate the use of cannabis on their territories. With that in mind, the Senate has adopted an amendment that clearly lays out the right of provinces to prohibit home cultivation.

As the bill heads back to the House of Commons to be adopted with or without the Senate amendments, the biggest question is the ultimate fate of the prohibition of home-growing operations by adults.

Ottawa’s initial plan was to let the courts decide whether or not federal legislation would trump the provincial law in Quebec and Manitoba in terms of home cultivation. Speaking in early May, Mr. Trudeau said he viewed home cultivation as a key measure to fight the grasp of organized crime over the cannabis trade in Canada.

“The decision on home cultivation of up to four plants was based on logic and evidence and it’s one that we will continue to establish as part of the federal framework,” he told reporters. “Criminal organizations make billions of dollars a year in profits on the sale of marijuana. We need to move forward on a system that controls and regulates while protecting our kids and our communities.”

Senator André Pratte, who proposed the amendment that would confirm the right of provinces to prohibit home cultivation, said federalism works best when the various partners have the leeway to try different approaches to meet common objectives.

“This is one of the amendments that senators feel is most important,” he said in an interview. “We will see how the government reacts to it.”

In a joint statement on Thursday night, the governments of Manitoba and Quebec called on Ottawa to confirm the discretionary power of the provinces.

“We urge the federal government to hear the Senate’s voice in order to avoid burdening citizens with the costs generated by unnecessary court challenges,” said Manitoba Justice Minister Heather Stefanson and Quebec Minister for Canadian Relations Jean-Marc Fournier.

Speaking to reporters on Friday, federal Health Minister Ginette Petitpas Taylor said the government will decide next week whether to accept all or some of the Senate’s amendments in the House.

“Within the next coming week or so, we will be able to make a decision regarding which amendments that we are going to accept and which that we won’t,” she said.

Justice Minister Jody Wilson-Raybould added that the government has created a system that will provide “safe access across the country to a legal source of cannabis and that includes home cultivation.” However, she refused to say whether the government will aim to reinstate the right to home cultivation across the land.

Many of the amendments adopted by the Senate were minor or technical, but a few others have raised concerns among the legal cannabis industry. In particular, producers are worried about changes to Bill C-45 that will hurt their ability to brand and promote their products, limit the potency of some of their products and force them to provide more disclosure on their investors than other legal industries.

“Some of the amendments offered in the final stages of debate will place the pioneers of our legal sector at a significant disadvantage in displacing illegal operators,” said Allan Rewak of the Cannabis Council of Canada.