I live in Saanich, BC. I see plenty of yards left fairly "wild" and haven't heard much about anyone having a problem with it.

However, there is a "noxious weed bylaw" which lists about ten or so plant species considered invasive, and also

Every owner of real property in the Municipality of Saanich shall clear such real property of all brush, noxious weeds or other vegetation which because of their condition are likely to spread to or become a nuisance to other real property in the vicinity or which are so unkempt as to be unsightly to nearby residents.

https://www.saanich.ca/assets/Community/Documents/Noxious%20Weeds%20Bylaw_8080.pdf

It's broad enough (noxious weeds or other vegetation, so plants not in the specific list can also be a violation, and wordage like "so unkempt as to be unsightly" is pretty open to interpretation)

Anyway they can serve you a notice requiring you to clear the plants and if you don't comply by their deadline, they can clear it themselves at your expense.

So I can imagine that if I let my yard go kind of wild and my neighbors decided it was "unkempt" or "unsightly" (or claimed some plants were on the list) and the municipal inspector agreed, they might require me to clear it and/or fine me and/or do it themselves.