Geraniums are best left till a little bit warmer. Take them from your storage and trim them right back. Take off all leggy stems. Plant them in potting soil and water lightly they do like cool conditions, sun can burn the leaves if exposed to suddenly, especially in a sunny window.If you have an area with light and not too cold they will do just fine. They do not need under lights.
Geraniums can also grow in part shade. Hope this helps!

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