On Wed, 5 Sep 2007 21:01:56 -0500, Paul Paulsen wrote:

Should most perennials be pruned to ground level=20
after a hard frost or is it best to wait until early=20
spring?

The standard rule is "clean up ASAP". When research has been done, it's
been found to be beneficial to leave the old leaves and stems as long as
possible.

Kay