PlantFiles: Early Goldenrod, Giant Goldenrod, Smooth Goldenrod, Tall Goldenrod, Verge d'or geante
Solidago gigantea

I have the cultivar 'Prairie Empress', though I'm not sure there's much difference. It seems to have a tendency to flop, and being as I have other goldenrods that I like better, I am leaning towards removing it before it gets a strong foothold. Blooms September-October in my garden.

I have had this kind of Goldenrod in my garden for over five years now. It is not invasive here. It has stayed where I planted it, never had volunteer seedlings. Old plants die back in winter, new ones come up in spring from the same root parts. Bugs and bees love the bright yellow blooms and flock around like crazy!

A lot of people hate goldenrod believing its pollen causes allergies. But the following is the truth:
"Goldenrod gets blamed for hay fever because the bright yellow flowers draw attention to the plant. But ragweed pollen is what causes allergy symptoms, not goldenrod.
Ragweed's pollen is lightweight and spread by the wind. Goldenrod's pollen is heavy and sticky and can't be blown by the wind. It is pollinated by insects. Unless you put your nose right into a goldenrod plant and sniff, you shouldn't be affected by its pollen."

A big, bold goldenrod that is a very common wildflower throughout the Great Plains and Midwest. Can be so aggressive that it is difficult to integrate into most gardens.