I suspect this is Steeplebush. I have another Steeplebush plant on my rooftop, but a full 50 feet or so away from this pot. Does Steeplebush self-sow...or maybe a bird made this all possible? ;-) But either way, I'm quite sure this must be Steeplebush...looks just like my other Steeplebush...the leaves are just ever so slightly different...

This next one....the pot is full of this plant... I believe I"d planted some yellow Cosmos at one point...might these be yellow Cosmos?

This next single plant was in the pot next to the pot above. Looks somewhat similar to plants above, but yet, the veins in the leaves aren't quite as pronounced...

No clue what this next one might be....

And here it is from another view....

#2 is Ageratina altissima, white snakeroot. Where is the location, and what type of plants are you growing? A side picture of #3 to see the plants form better would help and also the full underside of a leaf. Did you sow other seeds in pots and if so, then what species? #1 is Steeplebush.

Thanks, Jay. I'm growing these plants on a (full Sun) rooftop in Zone 6b, in NYC... Re: the white snakeroot, it must readily self-sow, then, as I surely didn't plant it...

But I'm curious....why do you want to know what other plants I am growing?...is there something I'm not understanding...or is it that you think #2 might not in fact be white snakeroot, but something else, and that you might be able to determine that once you know what other types of seeds I may have sown?.

I'll take more pix of #3 and add here...

Thanks.

#3 is growing in a pot, so you sowed Cosmos sulphureus seeds in the pot where the White snakeroot is growing, so it's natural to assume you might have seeded pot #3 also? I'm wondering what you are growing, so I have a better idea of what might be behind pot #3. It looks like a native plant, similar to Verbena stricta or a Vernonia species, but just speculating, it's probably neither. White Snakeroot is a very prolific seeder. I don't allow anywhere near my gardens.

Ah, ok..... so pot #3 has Summer Phlox in it (grown from bareroot stock). I think I may have had Black-eyed Susan seedlings in there as well, but they never seemed to take/thrive. May have thrown some Love in Mist seeds in there, but I know it's not that. Have licorice mint in pot next to it, but know it's not that either, in pot #3. I'll just have to take more pics, when I can...

do you sterilize your soil between years ...

https://tipnut.com/sterilize-soil/

is it possible this is old seed that all of a sudden sprouted??

some seeds can lay dormant for extended period of years ... mostly just to piss us off .. lol ..

ken

Lynn, if you take a picture of the leaf underside on plant #3, can you make sure the leaf is flattened and not curled, so we can clearly see the leaf edges. Thanks!