By Tom Schweich
Now blooming in Golden’s open spaces and private gardens with clusters of bright yellow flowers on short stalks above a mound of green leaves is “Sulphur-Flower Buckwheat” (Eriogonum umbellatum Torr. var. umbellatum).
Our plant is a quintessential Jefferson County plant because it was first recognized scientifically in Jefferson County by Edwin James, M.D. in 1820. The species is native to western North America from California to Colorado to central Canada, where it is abundant and found in many habitats. Because of its wide range and many habitats, there are a great many varieties. Six varieties are known from Colorado, and forty-one varieties are recognized by the Flora of North America.
Nearly all the Sulphur-Flower Buckwheats in Golden open spaces will be var. umbellatum. There is another variety, var. ramulosum, that Jim Reveal (2004) described from Mount Vernon Canyon on the southern edge of Golden and gave the common name “Buffalo Bill’s Buckwheat.” The most common garden cultivar found in most local nurseries is called “Kannah Creek,” originally from Grand Mesa in western Colorado. It is an excellent choice to start low-water gardening in sunny locations.
