Zone 7 generally stays frost-free until late October or later, so you can get away with slightly more delicate plants.
Plenty of summer annuals can be replanted in late summer or early fall, including: -Marigolds -Nasturtium -Petunia -Sweet pea
Depending on weather conditions, the UK can sit anywhere between USDA Zone 8 and 10, so any of the following plants will work there.
Some of the best include: -Daffodils -Dahlia -Tulips -Crocus -Iris -Hyacinth
While there’s a reasonable amount of temperature variation between Zones 9 and 11, the mildness of their fall season means we can group them together here.
You can grow pretty much anything mentioned so far. Some options for pretty potted flowers include: -Snapdragon -Verbena -Coral bells -Alliums