Well, I'm batting 1 out of 6, pretty poor! But I can tell you 100% that the last photo, #6, is a dahlia. I can't recognize any of the rest.

#1 MIGHT be a goldenrod???

#3 I think is a weed. Not sure which one, but it's a weed I always think is a flower in my garden till it blooms and I realize it's a weed. I think this is the same one I have.

#6 I agree looks like a dahlia.

Dee

These plants look similar to:
1)Verbena hastata
2)Silene dioica
3)Solidago sp.
4)Vernonia sp
5)Vernonia sp

#1 may, MAY, be some species of willow herb (genus Epilobium). I see these come up quite commonly as a weed in potted nursery stock and perennials. See if it develops tiny pink flowers followed by long, cylindrical, almost "pencil lead" thin seed pods that ultimately split open to reveal fuzzy, parachuted tiny seeds.

Could number 2 be cardinal flower?

All but #6 look like things I regularly pull from my beds, lol.

Could #2 be a penstemon? I also have yanked #1 & #3, so I hope they are both weeds.

I thought 6 was a dahlia, but the idea of it having overwintered in zone 6 was too much for me to comprehend! So, I'm excited about that.

No one thinks number 4 might be Lobelia cardinalis? That's what I'm hoping crops up there, lol.

I am leaning towards 3 and 5 being a weed.

Jury is still out on 1 and 2. The veins on mystery plant 2 are reddish. It's very low to the ground.

5, 4, and 1 could all be lobelia. Definitely wait until they bloom before passing judgment! None of them (except for maybe #2) has me more than 50% sure it is a weed.

I think that #5 looks a lot like my Lobelia cardinalis.

I'm almost 100% certain #3 is Horseweed (Conyza canadensis). It's one of those weeds that changes shape and form as it ages. In other words it starts out looking very different than it ultimately will look like when it blooms.

I was just Googling images for this one and found tons of 'em at all stages of development. I have it my garden. It's easy to pull, but it seems to be around every year no matter what I do.

Kevin

Dahlias overwinter easily for me in the Detroit area under mulch. And, given that last winter was one of the mildest ever recorded in E. North America, it's not surprising that one came back.