Some varieties of vinca are used to make a powerful chemical used in chemotherapy to treat certain forms of cancer.Here are some links to what flowers are edible that you can use: <a href="http://www.landofvos.com/articles/kitchen8.html">http://www.landofvos.com/articles/kitchen8.html</a> http://homecooking.about.com/library/weekly/blflowers.htm Ashley:August 12, 2008 at 6:28 pmI just want to know if cora vinca is an annual or perenial? patrick:January 22, 2