Mistletoe Man by Susan Wittig Albert (2001, Paperback, Reissue)

Susan does it again! Did you know there are THREE types of mistletoe? In Mistletoe Man you learn many fasts about mistletoe and other Christmas plants. Almost everything you want to know about mistletoe, except mistletoe (English kind) is an abortifacient. Meet Donna, Terry and their wacky Aunt Velda who has been given a trip around that galaxy, in first class no less, by the Klingon's. The hermit, jack of all trades, the Mistletoe Man, as he is called, is murdered, but by whom and how? Lots of motives! Aunt Velda takes a walk and discovers a mystery cave with arrowheads, Indian artifacts and gold (and a BIG surprise found in the next novel). A British women comes to work in Thyme for Tea and China and Ruby are once again drawn into a mystery involving a handyman with no visible means of support, a sports car driving nephew of a neighbor of the Mistletoe Man, huge greenhouse of marijuana, and wind up busted for drugs which turn out to be powdered sugar and oregano! The Whiz appears again to represent Donna suspected of being the murderer, but who really is? You'll be shocked to find out.