This book was probably from the 1970s or 1980s (I read it in the 1990s), and its hardcover was entirely covered in green vines (from what I remember). It was about an (alien?) plant that grew really fast and completely covered a family’s house. The members of the family are totally entranced by the vine, which seems to cast a kind of spell over them (and maybe even speak inside their minds?), until it is almost too late to do anything and they’re entirely trapped.