Is white vervain native to Toronto?
Thank you for your question about whether white vervain is native to Toronto.
VASCAN (The Vascular Database of Plants of Canada) is a great source for identifying if a plant is native to one of the ecoregions in Ontario. You’ll get the most accuracy if you use the botanical name to search. Verbena urticifolia goes by the name “white vervain” so I believe this is the plant you’re talking about. Broadly, this plant is indeed native to Ontario. There is more than one ecoregion in Ontario though. You can read more about ecoregions via the US Environmental Protection Agency.
The Native Plant Trust also confirms that white vervain is native to at least most of Ontario. They are another good source for native plant provenance