This plant have been through several frosts in zone 5b & still looks great. Does anyone know what it is please?

Thank you.

That's interesting, it looks like some kind of celery.

Johannian said:That's interesting, it looks like some kind of celery.

That IS interesting because I don't have any celery seed & there are 2 of these in my flower garden. The chickens were digging them up & I took some of the leaves & put them in water & one of them took root.

Hmm, that's strange. The thing that bugs me is that celery grows upright, and this one spreads out. Here are some pictures from the database:

The leaves are wrong for celery. I'm pretty sure it's not celery.

I think you're probably right.

Coreopsis grandiflora?

janinilulu said:Coreopsis grandiflora?

Thank you but the leaves don't seem to match that either.

Maybe a Bittercress relative? There are a bunch of cress that make small rosettes in the fall, then in the spring elongate, bloom and disappear by July. Some of the local cresses are Water Cress, Winter Cress, Bitter Cress, Hairy Cress and probably a dozen more.