Question
I understand that Plumbago is a 8b-10 zone plant.  I live in Warner Robins GA which is a 7b-8a zone.  Is there a chance that Plumbago would live and flower in my yard?

Answer
Donna,

You have asked a great question that many gardenners have concerning the USDA hardiness zone ratings of plants.  

The USDA hardiness zones indicate the average low temperature an area can expect to experience during any given winter.  The plumbago you are talking about is hardy to 8b which represents a low temperature of 15-20F.  We do not worry about the 10 rating, it is the low temp that is important.  In GA, zone 8a, where you live is a bit cooler at 10-15F.  I would say give it a try since there is some overlap.

But let's say your plumbago is not hardy at your location.  That does not mean you couldn't grow this plant.  I would treat it as an annual plant.  And this goes for many wonderful plants that gardeners do not grow because they are not hardy.  

We get caught up in the terms annual or perennial.  Most of the our bedding plants that are considered annuals are perennial in the part of the world where they evolved.  

So I say plant plants you like, don't worry if the label says perennial, and have a beautiful yard.

I hope this helps.

Good luck in the garden.

Gary