Answer: If you have a very bright window sill, or supplemental lighting, you might be able to keep them growing and blooming indoors. Bring them inside before temperatures drop below 50 degrees.
However, many gardeners are short on indoor growing space and need to store their container plants during the winter instead. To store them, you need a place that is cool -- under 45 degrees -- but above freezing. It may be dark or light. Store the plants there until spring. Water only as needed to keep the soil from drying out completely -- very little.
For storage, leave the roses outside this fall so they stop growing and start resting. Frost will not damage them. In spring when the worst of the winter has passed, set the roses outside to wake up naturally with the season.
Bring the geraniums into storage when temperatures are in the mid forties. Wait until temperatures are reliably above 45 degrees to set the geraniums outside again.
The gerber daisies are very difficult to grow long term under home conditions, I would suggest replacing them next spring if you like them.
You will have to bring the geraniums indoors one way or another, to a bright sunny spot or to storage. The roses however might survive outside if you can insulate the roots, similar to the way they would be insulated if planted in the ground. To do that you could try heaping mulch over and around the pots, or set the pots in a styrofoam cooler or similar container and pack oak leaves or straw or mulch around them as insulation. Once temperatures are consistently below about twenty degrees, remove any remaining foliage and wrap the canes in burlap and stuff it with the dry insulation material. Finally, you could top it with some plastic to help keep it dry but do not enclose it completely -- you do not want to trap condensation inside. Store the insulated rose in a consistently shady spot such as on the north side of a building. Water as needed to keep the soil barely moist--do not let it dry out completely. Also check them periodically for signs of rodent damage.
Another option would be to sink the rose pots up to the rim in the ground and mulch around and over the roses. If you have a gardening friend with a bit of space where you could "plant" them temporarily in their pots, that might be your best option. Do this in late fall but before the ground freezes and bring them home in spring when temperatures begin to moderate.
Good luck with your flowers this winter!
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