Hello, we found this plant in our garden and left it alone, it is growing big but we don't know what it is. It grew all by itself, we did not plant it. Attached are some images. Location is Canada, Toronto.
I'd suggest you get up out of bed and pull it out immediately. I don't wish to eradicate any plant or animal, but this is ragweed and will be causing people some misery in a matter of hours, maybe days. Really. You won't even notice it blooming, it's so nondescript.
Ok thanks, will pull it out today. Never seen one before. Just out of curiosity, how do these plants propagate, I never planted it so how did it get there?
Wind borne pollen, and very light weight seeds that can come in on anything: your jeans hem, sneaker tread, dog's paws or fur, a briefcase, a shopping bag, bird wing. They persist in the soil so a squirrel scratching at the surface may have inadvertently turned up a few seeds that had been there for years. Sometimes with weeds it's best to not ask, "Why?" but instead ask, "Why not?"
