Some laws in the states say plant numbers are when plants are in flower. But in Canada it says plants in any stage of growth.
Here is a copy of Bill C-45
Cultivation, propagation and harvesting — 18 years of age or older
(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
(b) more than four cannabis plants at any one time in their dwelling-house.
Cultivation, propagation and harvesting — dwelling-house limit
(5) Unless authorized under this Act, if two or more individuals who are 18 years of age or older are ordinarily resident in the same dwelling-house, it is prohibited for any of those individuals to cultivate, propagate or harvest any cannabis plants if doing so results in there being more than four such plants being cultivated, propagated or harvested at any one time in the dwelling-house.
Cultivation, propagation and harvesting — 18 years of age or older — without authorization
(6) Unless authorized under this Act, it is prohibited for an individual who is 18 years of age or older
(a) to cultivate, propagate or harvest any cannabis plant at a place that is not their dwelling-house or to offer to do so; or
(b) to cultivate, propagate or harvest any living thing, other than a cannabis plant, from which cannabis may be extracted or otherwise obtained, or to offer to do so.
Cultivation, propagation and harvesting — young persons and organizations
(7) Unless authorized under this Act, it is prohibited for a young person or an organization to cultivate, propagate or harvest any cannabis plant or any other living thing from which cannabis may be extracted or otherwise obtained, or to offer to do any of those things.
Definition of dwelling-house
(
For the purposes of this section, dwelling-house, in respect of an individual, means the dwelling-house where the individual is ordinarily resident and includes
(a) any land that is subjacent to it and the immediately contiguous land that is attributable to it, including a yard, garden or any similar land; and
(b) any building or structure on any land referred to in paragraph (a).
Punishment
(9) Subject to section 51, every individual who is 18 years of age or older who contravenes any of subsections (1), (4), (5) and (6) or any organization that contravenes subsection (1) or (7)
(a) is guilty of an indictable offence and is liable to a term of imprisonment of not more than 14 years; or
(b) is guilty of an offence punishable on summary conviction and is liable
(i) in the case of an individual, to a fine of not more than $5,000 or imprisonment for a term of not more than six months, or to both, or
(ii) in the case of an organization, to a fine of not more than $100,000.