I’ve had a geranium plant for several years. Every spring I put it outside and it flourishes. Every fall I bring it inside and it goes a bit dormant, but still manages to flower now and then, though some of the leaves shrivel and go yellow, then brown. Almost every time I water it through the winter I trim off the dead leaves, dropping them into the large pot that holds the plant. They crumble and eventually become nourishment for that old geranium.
