tiarella

Rattlesnake-master
Photo credit

Krzysztof Ziarnek, Kenraiz, CC BY-SA 4.0, Original photo, Wikimedia thumbnail; no crop or retouching

Rattlesnake-master

Eryngium yuccifolium

Grows in pots
Flower color
Blue, green or white
Bloom
Summer
Height
4–6 feet
Spread
3–6 feet
Light
Full sun
Soil moisture
Somewhat dry to moist
In pots
Yes

Native to Tennessee (state-specific source)