https://www.justice.gc.ca/eng/cj-jp/cannabis/
"grow, from licensed seed or seedlings, up to 4 cannabis plants per residence for personal use"
Although I agree, this will rarely be enforced, and in some cases unenforceable (depending on how loud and flagrant you are about growing unlicensed strains.
Edit:
Also from the Act:
https://laws-lois.justice.gc.ca/eng/acts/C-24.5/page-3.html#docCont
(4) Unless authorized under this Act, it is prohibited for an individual who is 18 years of age or older to cultivate, propagate or harvest, or to offer to cultivate, propagate or harvest,
- (a) a cannabis plant that is from a seed or plant material that they know is illicit cannabis; or