I know that you let the foliage on bulb plants turn brown before cutting them
back, in order to put strength back into the bulbs.
What about other plants, for instance the Oriental Poppy? Soon after the blooms
are gone, the foliage looks like hell and starts "dying" back. Should these
plants be allowed to look bad for awhile, or is it OK to cut them back when the
blooms are gone? Any other plants that have to prepare theirselves for next
year before you can do anything to them?