The classic one is Canada goldenrod, Solidago canadensis. It's big. It's bold. It's beautiful. It's...vigorous. In fact, lots of people don't like goldenrods because they assume that all goldenrods are going to act like Canada goldenrod, which likes to expand its territory by sending out horizontal rhizomes. Lots of horizontal rhizomes, from which come tall, vertical stems. One plant rapidly becomes a large clump of many plants. (There are some hybrid cultivars of this species available now, selected often for both smaller size and less invasive tendencies. They are gorgeous, well mannered, and they make excellent garden flowers.) Canada goldenrod can be wonderful in the wild, though, where large swathes of it create golden pockets along the roadsides and in the fields. Its glorious yellow blossoms seem to support an entire community of insects...but that's a good subject for another post.
Another goldenrod that is currently in bloom is stiff goldenrod, Solidago rigida. When both the common name and the scientific name agree on a characteristic (in this case, stiff or rigid), it's a sure bet that something about the plant will be obviously described by the characteristic mentioned. With stiff goldenrod, the stems are very upright, the flowers are fairly flat-topped, and the leaves are particularly stiff when you feel them. The whole plant screams rigid, in fact, especially when compared to a looser textured goldenrod like the elm-leaved goldenrod. Whether this seems like a Type A plant or not, it's showy, well-mannered, and fun to include in the flower garden. I have a few in the front flower bed, and one lone plant in the back five acres.
The last species I'd like to talk about in this post is Fireworks goldenrod, Solidago rugosa 'Fireworks'. Fireworks goldenrod is one of those plants that you can't forget if you've ever seen it in bloom. It works best in masses, I think, but it takes special placement to make it seem graceful, rather than overwhelming. This photo isn't from my yard, but I think the homeowner (a landscape architect) has used this plant particularly well, wrapping it around the base of a redbud on a slope where it seems to spiral upwards, leading you along the path and providing movement to the planting bed. Solidago rugosa, wrinkled leaf goldenrod, is actually not native to Kansas, but is native in Missouri and further east. Fireworks, however, seems quite at home in this area, both culturally and aesthetically.
Don't all of these gorgeous, sunshiny yellow blooms just lift your spirits? Goldenrod is a great plant!