Missouri Evening Primrose

10" tall x 18-24" wide (seed propagated). This native wildflower is
renowned for the huge 4" yellow flowers that open each afternoon and
close up the following morning. Long blooming throughout the summer
months, it keeps going until it feels it has set enough seed pods to
retire for the season. Long-lived, it forms a huge underground tuber to
keep itself going from year to year. Evening Primrose cascades nicely
over rocks and retaining walls. (Botanists have changed the name for
this species from missouriensis to macrocarpa).