... in plant sociology, these are "herb communities":
http://www.ufz.de/biolflor/overview/merkmal.jsp?ID_Merkmalsg...But in a more general sense, you can speak of "wild herb meadows" which is basically the same as "flower meadows"; that is because most wild flowers
are herbs, i.e. perennial plants which flower once or twice every year, and are considered "weeds" in other contexts.
http://books.google.com/books?id=Ky-WVGIqkWAC&pg=PA49&lpg=PA...(There are also annually flowering plants which may form a community called "flower meadows" of a different type.)
I know something about these things because I do some green rooftop gardening :-)
peer agreement (net): +5