Nodding Bur-Marigold Seeds (Bidens cernua)
A handsome and interesting fall-blooming plant for damp, and sometimes challenging locations.
An annual sunflower-relative, nodding bur-marigold naturally occurs around marshes, river backwaters, and locations that are prone to seasonal flooding. In fact, for many years we grew this as a garden plant around the downspouts of our house where it thrived. Its preference for such locations makes it a great rain garden plant, but more than that -- this species has exception potential for urban stormwater bioswales – requiring neither pristine conditions, nor coddling. (For comparison, nodding bur-marigold prefers roughly the same habitat conditions as wapato, sneezeweed, and softstem bulrush).
The flowers of this plant appear in late summer, continuing into cool weather, then nodding as they age (hence the name). After flowering, the plants produce awned seeds that attach themselves to animal fur and feathers for transport into other favorable locations.
Despite its annual lifecycle, nodding bur-marigold re-seeds itself fairly well in optimal locations, and can approach 3-feet in height, although in our experience it remains shorter in semi-shaded conditions. Additionally the leaves tend toward a purple color in partial shade.
This is an important wildlife plant. Numerous bee species are attracted the flowers, and a number of small butterflies and moths use this as a caterpillar host plant. The seeds are consumed in large numbers by ducks.
Nodding bur-marigold is native to most of temperate North America.
Approximately 50 to 100 seeds (0.5 grams).