Answer: Of the plants you've listed, only a few are winter hardy in your gardening region. And, because they are in pots where the roots will be subjected to cold (as opposed to being in the ground where they would be somewhat protected), you'll need to provide some winter insulation. Scotch broom, clematis, hardy hibiscus, chrysanthemums, camellia, St. John's Wort, and rhododendrons should be fine in their pots outdoors if you gather all the pots together, set them on a couple of inches of insulation (I use the styrofoam sheets for wall insulation you can get at Home Depot. The sheets are about 2" thick. Cut it as necessary.) After setting the pots on the sheet of styrofoam, tape 4 sides so it looks like a bin. Then pile shredded leaves, compost, or even styrofoam peanuts into the bin, over and between the pots. This will help keep the roots from freezing solid. Your tropicana and bleeding heart plants will die down after the first frost and you can dig the roots/bulbs and store them in a cool place that remains above freezing. Your mandevilla, geranium,tropical hibiscus, jasmine and orange marmelade are tender and will need to grow indoors over the winter months.
Best wishes with your garden!
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