If you're planning to over-winter your geraniums & pelargoniums please "take with a pinch of salt" anything you hear from well meaning "experts" – often they know an awful lot about a wide range of plants and limited specific knowledge of each species.
If the plants are warm and in good light, they are very likely to continue to grow, and some will even flower, in the winter. So fill all those sunny windows and conservatories with all your members of the pelargonium family!
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