For several years I would bring the summer glorious geraniums into the basement where they mostly died because I did not allow them to go dormant. This winter I trimmed them back to the most sturdy of branches and put them, pot and all,into the cool crawl-space under the house. Once a month I gave them a small drink (Don't we all need that in the dark winter months?) and kept them in the dark. From late October until mid-April they stayed in that environment. They had sprouted a few pale, spindly branches but the main plants were in great shape (no leaves of course). It is still a little early to have them outside but I did put them out into the sunny patio area after a small trim. In a week they have started sprouting new leaves and will actually look like nice plants in short order. A little slow release fertilizer and I hope to have nice no cost geraniums for summer.
Happy planting and welcome to spring!