Do a google.com search for RUELLA. It's hardy to zone 8, so you can pot it up and grow it in a sunny window this winter.

This is one tough plant! I didn't know until recently that they come in three different heights and also a "creeping" variety. They throw seeds all over the place, so give them plenty room. They are also very easy to propagate. I have the tall purple/blue (about 4'), short white (8") pink - tall, short and med (abt 18") tall. I assumed they would all grow to full (tall) size the next couple of years, but a lady at the nursery where I purchased the tall pink told me about the different varieties. I'm still looking for the tall white. Every morning they are full of blossoms and by late afternoon, the blooms are on the ground (on the tall ones). The short dead blossoms are just lying on top of the foliage, which doesn't look so great. I have a ton of short ones to get rid of. I have thrown so many away, they multiply like crazy, as well as dropping seeds everywhere. Hummingbirds, bees and butterflies love them. The seed pods explode when they are ripe.

It's a cold-tender perennial. In Arizona it dies to the ground in a hard frost and resprouts in the spring.

It spreads through moist soil by underground runners, so be careful where you put it.

i have the purple it roots easy in water out side in the southern heat it loves it . mine stays out with twenty degree weather just cover it good with leaves during winter. they pretty tough plants signed tropical breeze