The Yankee part of me has a hard time watching my plants die in the fall/winter. Whenever possible, I try my hand at bringing a few inside. So I can let them enjoy a long, slow death. Frankly, I'm amazed this Basil has lasted until February.
Tips for Wintering Basil Indoors:
(please note I have followed almost none of these and it's still alive)
-Keep in a sunny window. But not too sunny so that the air is dry. Or too close to the window or the cold will result in black leaves. Good luck.
-Plant in loose, well-draining soil. Keep the soil moist (not wet, not dry). This is stressful.
-Do not let it flower. Because then the plant puts all of its energy towards the flowers/seeds and none towards the yummy leaves.
I'm of the "do as I say, not as I do" school of gardening. In the name of science, I am pruning off those flowers tonight and am going to water more regularly. Let's see if this little bugger rebounds with a little TLC.