Jack kindly sent in this idea:

"Most people buy the white or red grapes to snack on. They are a healthy snack.  However they are more. Be careful pulling them from the stem. Dry the stems (usually 24 hrs is enough) put some school glue, hot glue or almost any adhesive and apply the 'moss' available in most any craft or mega stores for very few dollars. The trees look natural and no two are alike."