Geraniums make decent houseplants if you can provide them with lots of bright light. They like a cool temperature, so even if you keep your thermostat low, they should be happy. However, they’ll start to look gangly and gawky if you don’t provide enough light. There are a few techniques for winterizing geraniums, with or without a pot.
To winterize your beloved geraniums in a dormant storage phase, dig up the entire plant before frost and gently shake the soil from the roots. Place the plants inside open paper bags or hang them upside-down from the rafters in a cool, dark location for the winter.
When saving geraniums for the winter in pots, dig up your geraniums and place them in a pot that can comfortably fit their rootball. Prune the geranium back by one-third. Water the pot thoroughly and place in a cool but well-lit part of your house.