Amsonia hubrichtii, the threadleaf bluestar, is one of my favorite plants. It was not well known among gardeners until the Perennial Plant Association named it the 2011 Plant of the Year. The species was discovered in 1942 by Leslie Hubricht growing in the Ouachita Mountains in central Arkansas. The species was later named in her honor.
Each plant has ornamental qualities that make it stand out from other perennial wildflowers. In May and June, clusters of small powder blue, star-like flowers top the strong stems. The stems are encircled with soft, narrow leaves resembling pine needles, making each plant look like a small shrub with feathery texture and incredible fullness. I have found them to be extremely hardy, drought tolerant and very low maintenance.
The real show develops in September when the foliage turns a butter yellow fading to a golden brown by October. One specimen plant is spectacular in each season of the year, but a group of ten or more massed together and strategically located are quite stunning. Individual plants can reach up to 48 inches tall and 24-36 inches wide. They prefer full sun to partial shade and an average garden soil.
This summer I have only watered them 3 times, so they are tough. At the arboretum, they are planted along the east border paths. Amsonia hubrichtii is a dynamic perennial that deserves a place in your garden.
Other Amsonia are just as ornamental, but offer different textural elements and sizes for just about any sunny to partial shade landscape setting. They are Amsonia illustris, Amsonia ‘Blue Ice’, Amsonia cilliata and Amsonia rigida.