Monday, July 12, 2010

Native Plant of the Week: Cup Plant ~ Silphium perfoliatum

Cup Plant is considered one of the best native plants for wildlife due to its size (cover & habitat), seed production (food), flowers (nectar) and capacity to hold water in its leaves that join together around the square stem.


It can reach heights of 10 feet tall or more in rich soil and abundant moisture. At the moment in our yard, it is almost at nine feet with the above average amount of rainfall that we've had this season.


The flower starts blooming in July and is bright yellow in color. It is several inches in diameter and makes a very nice colorful addition to the garden.
We see many types of butterflies nectaring on the flower, monarchs mid summer and tiger swallowtails in late summer. After a rainfall the leaves hold a significant amount of water and there will be many types of insects that will come and drink, as well as smaller bird species.


According to Prairie Moon Nursery's Website, "Cup Plant is quite easy to grow in average garden soil and in diverse prairie plantings in heavier or wetter soils. It can be readily started from seed by fall planting outdoors, or, if planted in spring, a period of 60 days of moist, cold stratification for 60 days is recommended prior to sowing."


Image: Steve Hurst @ USDA-NRCS PLANTS Database
Cup plant seeds are quite large (almost the size of a sunflower seed) and provide a generous amount of protein to birds and other wildlife who seek out the seeds in fall. We often scare up many birds walking by our cup plant, the chickadees and gold finches especially in the fall.




Because of the large amount of growth and mass that the plant can create in one season, it has been studied as a possible perennial crop for use in the production of biofuel and carbon storage.
Two examples:

It has also been used as an alternative livestock forage crop.


Cup Plant is native to the Dakotas east to the Atlantic. See map.

Image Source: USDA Plants Database