I know this looks like a 'jumble jungle"? right now, but it is one of my smarter seasonal set-ups. The plant in the very back against the fence is my goatsbeard (Wiseacre) .. very tall white astilbe looking plant .. in the middle are the oriental poppies .. and in front is the season long is a Pink Weigela .. So what happens is a layered affect. The poppies are stunning when they reach full height and have those wonderful deep red, black centered flowers .. as they die down and get really messy the weigela hides it from the front .. the goatsbeard covers it from the back .. it sounds simple and straight forward ... because it is ! I try very hard to plant in succession to keep the garden looking as nice as possible without killing myself with work ! : )
P.S. towards the marble rocks is a beautiful Purple Flame Grass for contrast in plant material and colour .. a great Autumn pick me up !