leaf and stalk

Appears to be Verbena bonariensis.

A short-lived perennial which seeds profusely. Lovely to watch it swaying in the breeze but be certain to deadhead regularly

I have noticed the leaves turn whilte , almost looks like it is dusted with white powder?? Is that normal?

Powdery mildew? It could be too wet or too dry (probably too wet), adjust the water and see if that helps.

A whiteish dusting on a plants leaves when temperatures are between 60 and 80 degrees F, and most often during dryer weather, could well be Powdery Mildew. Many plant are susceptible, but when conditions are favorable most plant could get it. The spores that become Powdery Mildew are spread around by the winds.
I have found that either a 50/50 mixture of fat free milk and water or 1 teaspoon of baking soda mixed into 1 quart of water will help control this mild plant disease.

I don't know about the rest of youall, but powdery mildew is already so prevalent here this year that I dread even planting squash. Normally we don't get a lot of this fungus until much later, but this year even Columbines are showing signs of it. The usual vectors in the environment (the Lamiums like Henbit) are already in decline. And it's only April!

I think it is quite pretty for a weed. Sorry I am not any help, just wanted to give my two cents. Good luck.

This is one of my favorites; and the skippers in the fall love it too, covering the blooms. I pluck/crush the seed heads in late fall and scatter just throw them all around. The powdery mildew is an eyesore. In my yard/NJ, they don't start their show until the summer.

These are blooming here now. One of those "think I saw" flowers. Think I saw something purple... Also see-through, if in front of other plants, you could still see the ones behind. Enough in the wild to satisfy my eyes, no urge to "have" any.