We were away from mid-October to November, but before we left I took a couple of photos of plants that were still blooming well. The dry, sunny start to the month helped a lot to keep perennials going longer than usual.
Lobelia cardinalis 'Queen Victoria' has a brilliant red flower and contrasting purple foliage. I grow it with Salvia 'Black and Blue', whose broad green leaves and black stems are a good complement. The cobalt-blue flowers of the Salvia, not visible in the photo make a stunning combination.
The small blue flower in the background belongs to Clematis x durandii, sprawling among the leaves of a dwarf oakleaf hydrangea. Here's a better look at it, trailing over a hardy geranium: